Development of pest and nutrient management strategies for hop production in the Northeast

Final report for LNE16-348

Project Type: Research and Education
Funds awarded in 2016: $161,412.00
Projected End Date: 10/31/2020
Grant Recipient: University of Vermont
Region: Northeast
State: Vermont
Project Leader:
Dr. Heather Darby
University of Vermont Extension
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Project Information

Summary:

There are more than 350 acres of hops in the Northeast (NE) with hop yards ranging in size from 0.25 to 25 acres. Hop yield and quality is often limited by pest and fertility issues. This is a new industry in the Northeast and growers need proper introductory education, which will have a direct and significant impact on regional hop yield. We hypothesized that grower education on sustainable pest management and grower collaboration on nutrient management recommendation development will increase NE hop yield. Pest management research trials included a biocontrol impact study, a hop downy mildew (DM) crowning trial, and a variety trial of regionally collected hop germplasm. In addition, a nitrogen management trial evaluated rates and timing and the subsequent impact on yield and quality. A robust outreach and education program was developed and deployed to share information with producers to reduce pests and improve yields and quality.

Fungal diseases are a top concern in NE hop production. The regional climate offers ideal cool and wet weather that is optimal for hop downy mildew and secondary infection of other diseases. Downy mildew has been present in all scouted northeastern hop yards. To prevent downy mildew and reduce the amount of disease inoculum, farmers use several methods of primary basal spike removal called crowning. These methods have not been evaluated for efficacy in the northeast. While increased pressure from downy mildew in this region gives us more to gain by crowning to remove overwintering downy mildew, our much shorter growing season makes the timing of this practice tricky. Our research indicates that there are benefits to crowning and that it is important to implement this practice as early as possible in the spring (mid-early April). If hops can be crowned in early to mid-April hop yields could be increased over 300 lbs per acre.  This trial has also confirmed the risk of crowning too late (mid to late May): crowning seems to be helping to manage downy mildew pressure, but crowning after shoot emergence can reduce yields by shortening the growing window. In some years, yields were reduced by 100% if crowning occurred towards the end of May. Ultimately, farmers need to decide on a year by year basis if it makes sense to crown hops based on spring weather.

The high-intensity Pacific Northwest hop industry has made several conventional fungicides and insecticides available for use on hops. Many farmers are concerned about the impact these products have on beneficial organisms. Through this project the goal was to evaluate how beneficial insects can impact pest populations on 3 different farm management types (organic, low, and high pesticide management). The open treatments in the study allowed for natural enemies to prey on the hop pest populations whereas the excluded treatment kept natural predators away from the pests. Hence, it is expected that a decrease in pests in the open treatment would be a sign of predation due to populations of natural predators. An increase in pests in the open treatment may indicate an absence or low abundance of natural predators. There were some distinct differences between open and closed treatments, especially in the low to no-spray environments. In environments with low pesticide usage, the beneficial insect population was able to control 65 to 95% of the hop aphid population. In the high pesticide usage environment, beneficial arthropods did not have any impact on pest populations. Environments with decreased insecticide applications, had lower pest populations after one week of exposure versus those closed off from the environment. Conversely, on farms with more use of insecticides there was more often no effect in insect populations between treatments. In a more diverse low-spray environment, there is the potential to see more of an impact from predation of hop pests by natural enemies.

Eleven lines of landrace germplasm were collected from known sites in Vermont, Massachusetts, and New York and propagated in a variety trial. The goal was to evaluate local germplasm that has evolved over the past 150 years and has potentially developed resistance to major pests. Initial collection and propagation spanned over the years of the project and initial data was collected on eight of the eleven lines. The landrace varieties including Kingdom, Wolcott, Peacham002, and Mount Toby all showed less pest pressure compared to the other lines collected. In addition Northfield 001 and Wolcott 001 had the highest yields although only evaluated for first year production. Quality was unique for all varieties indicating they likely were derived from unique parents. Further investigation will continue to identify if these lines can potentially be directly released to farmers in the area.

In drier climates of the Pacific Northwest, hops require significant quantities of nitrogen and it has yet to be determined best nitrogen rates for hops grown in the temperate northeast.  In 2019 and 2020, nitrogen rates between 150 and 200 lbs per acre led to the highest total plant nitrogen (2.26 to 2.44%). This indicates that this range of nitrogen fertilizer likely will be needed to maximize yield. However, experiments did not show a yield response to increasing nitrogen rates. This may have been a result of other environmental factors such as drought. There were some slight similarities between 2019 and 2020 when looking at hop brewing quality. 2019 treatments appeared to illicit a more pronounced, negative response to increased nitrogen applications as both alpha acids and beta acids appeared to decrease when looking primarily at nitrogen treatments.  Some similarities were observed in the 2020 Cascade hops as well as beta acids overall, suggesting that excessive nitrogen rates may negatively impact levels of hop resins. Other similarities were observed across years with highest hop aphid populations present in those plants receiving 200 lb N ac-1 of total nitrogen. The use of an in-field nitrate meter could have the potential to become a useful tool with quick results. This would require some additional work to determine nitrogen fertility requirements corresponding to petiole nitrate readings for this crop. Nitrogen rates, timing, and tools to properly manage are needs for future hop research.

Our educational approach included numerous conferences, field days, webinars,  and written materials posted on the web (www.uvm.edu/extension/nwcrops/hops). In addition, a bi-weekly scouting survey (goScout) was combined with a virtual “ID Hour” to help farmers learn and adopt new pest and fertility management tools. Throughout the project period, education was provided to 891 farmers and 323 service providers throughout the region and the country. 53 farms representing 142 acres adopted a new strategy to manage pests or fertility on their farms. These farms reported increases in hop yield ranging from 50 lbs per acre up to 800 lbs per acre. The impact per acre ranged from $650 to $10,400 depending on the farm.  

Performance Target:

PERFORMANCE TARGET
Forty farms in the Northeast will adopt at least one new pest and/or nutrient management practice on a total of 100 acres and as a result their average hop yield increases by 400 lbs per acre resulting in a increased gross revenue of $6,000 per acre.

 

The overall goal of the project is to develop and deliver region specific pest and nutrient management practices to increase hop yield in the northeast.

Objective 1: Develop region specific mechanical control strategies for managing downy mildew in hops.

Hypothesis 1: If the most effective crowning method is identified, then the amount of inoculum will be reduced and hop yields will increase.

Fungal diseases are the primary concern in northeast hop production. The regional climate offers ideal cool and wet weather that is optimal for hop downy mildew. Downy mildew has been present in all scouted northeastern hop yards. To prevent downy mildew and reduce the amount of disease inoculum, farmers use several methods of primary basal spike removal. The most effective methods have not been identified in the region.

 

Objective 2: Quantify the impact of natural enemy arthropods on pests in northeast hopyards.

Hypothesis 2: If the ability of natural enemy arthropods to combat pests is quantified, hop growers will encourage these populations, reduce losses from arthropod pests, and increase yields.

The high-intensity western hop industry has made several conventional fungicides and insecticides available for use on hops. Many farmers are concerned about the impact these products have on beneficial organisms. Also, we have observed broad-spectrum insecticide sprays to cause secondary outbreak of spider mites. These outbreaks cause more devastating yield and quality loss than the target pest. We propose to quantify biological control services in hop yards of varying agricultural intensity.

 

Objective 3: Screen wild hop germplasm for unique pest resistance and quality characteristics.

Hypothesis 3: If wild hop rhizomes are collected, pest resistance and/or unique quality characteristics will be identified.

Currently hop growers plant cultivars selected for regions with different climates and high-input practices. Many cultivars in demand from brewers are proprietary and unavailable to growers in our region. Additionally, the commercially available cultivars that are less susceptible to mildew are still subject to economic losses due to yield reduction from disease. It is critical that we begin an active cultivar evaluation of historic germplasm to identify potential pest and/or unique aroma varieties.

 

Objective 4: To develop optimum nitrogen rates for hops in the northeast.

Hypothesis 4: If growers apply optimum nitrogen rates then yield and quality will increase.

Northeastern hop yield is lower than other production regions and we have learned very little about hop fertility management. Research has shown that the effects of N fertility on hop quality characteristics are conflicting (Brooks and Keller, 1960); one recent study indicated an inverse relationship between soil N availability and hop quality (Ceh, 2014). Also, there is a lack of available hop industry knowledge. We worked to create a hop nutrient management plan and compare methods of testing for plant tissue nitrogen that farmers can easily conduct in the field themselves. Also, we will educate and provide guidance to farmers on how to conduct soil sampling and interpret test results.

Introduction:

Problem

Pest Management: Fungal diseases are a top concern in NE hop production. The regional climate offers ideal cool and wet weather that is optimal for hop DM and secondary infection of alternaria and phomopsis. Downy mildew has been present in all scouted northeastern hop yards. To prevent DM and reduce the amount of disease inoculum, farmers use several methods of primary basal spike removal. These methods have not been compared and it will be valuable to pinpoint the most effective method. The high-intensity PNW hop industry has made several conventional fungicides and insecticides available for use on hops. Many farmers are concerned about the impact these products have on beneficial organisms. Also, we have observed broad-spectrum insecticide sprays to cause secondary outbreak of spider mites on several farms. These outbreaks cause more devastating yield and quality loss than the target pest. We propose to quantify biological control services in hop yards of varying agricultural intensity.

Both small (0.25 acre) and large (25 acre) hop growers plant cultivars selected for regions with different climates and high-input practices. Many cultivars in demand from brewers are proprietary and unavailable to growers in our region. Additionally, the commercially available cultivars that are less susceptible to DM are still subject to economic losses due to yield reduction and the impact that the mildew has on cone quality. It is critical that we begin an active cultivar evaluation of existing and emerging hop varieties and gain a better understanding of biological control services. Both are potentially less expensive, more environmentally sound management options.

Fertility Management: Northeastern hop yield is lower than other production regions and we have learned very little about NE hop fertility management. Research has shown that the effects of N fertility on hop quality characteristics are conflicting (Brooks and Keller, 1960); one recent study indicated an inverse relationship between soil N availability and hop quality (Ceh, 2014). Also, there is a lack of available hop industry knowledge. NE hop growers want to participate in the development of regionally appropriate N application rate and timing information. 

Growers in the Northeast do not have the decades of experience growing hops that can be found in the PNW, and can often be found spraying broad spectrum pesticides without consideration of economic thresholds or beneficial insect populations.  To avoid insect pressure and ignorance putting a quick end to this fledgling industry, research and outreach must be developed on integrated pest management specific to our region. The objective of this project was to work collaboratively with growers to identify beneficial and harmful insects attracted to hop plants in the Northeast and to help farmers adopt IPM practices.

Solution

Our surveys and on-farm observations indicate that farmers need more pest and fertility management skills and recommendations. Extension work and education has started to help, shown by our 2015 hop conference survey results. Thirty-eight people said that UVM helped them start or expand their hop yard, 40 said that UVM helped them with pest scouting and 37 said UVM helped them with disease management. Twenty-two people said that it was “very true” that UVM helped them improve yields, while 19 said that this was somewhat true. While the work we have done so far has been helpful, we need to continue our research and outreach efforts to help farmers grow a better crop.

Our educational approach created a research- and experience-based education curriculum. Participants participated in the project by utilizing the factsheets and “ID Hours”, and attended conferences and workshops. The “ID Hour” and “goScout” survey helped to track and reflect farmer progress and participation.

The research trials coincided with our farmer education curriculum. Research evaluated crowning dates and developed best practices to reduce the amount of hop DM primary inoculum. On a gradient of intensity, natural enemies attacking the major NE hop pests in three hop yards was quantified.  Nitrogen application rates and timing were evaluated to determine the impact of hop yield and quality.  Germplasm was collected from known sites in the Vermont landscape and grown out at Borderview Farm in Alburgh, VT in a variety trial. Local germplasm that has evolved over the past 150 years has potentially developed resistance to major pests.

We helped growers improve yield by implementing a robust research and education program. 

Cooperators

Click linked name(s) to expand
  • Roger Rainville (Researcher)
  • Gene L'Etoile (Researcher)
  • Kathleen Norris (Researcher)

Research

Hypothesis:

We hypothesized that grower education on sustainable pest management and grower collaboration on nutrient management recommendation development will increase NE hop yield. Pest management research trials included a biocontrol impact study, a hop downy mildew (DM) crowning trial, and a variety trial of regionally collected hop germplasm. A nitrogen management trial included rates and timing was conducted. To better gear hopyards for fertility management and plant health, contributing to pest defenses, soil sampling and test reading were offered.

Materials and methods:

Hop Germplasm Study

Wild hop plants were initially collected from eight locations within Massachusetts, New York, and Vermont in the fall of 2016 (Figure 1). In May 2018, new rhizomes were cut and further propagated from nursery yard at Borderview Research Farm in Alburgh, VT.  In May 2019 three additional varieties were propagated and later planted into research plots at Borderview Research Farm in Alburgh, VT.

When sampling each germplasm source,  multiple rhizome cuttings, approximately 6” in length, were taken from each line, placed in plastic bags and kept in refrigerated storage. Cuttings were occasionally inspected for spoilage and any compromised samples were discarded. After three months of cold storage, the remaining cuttings were planted into 4” pots with Farfard 3B potting media (Kent, New Brunswick) at the UVM greenhouse. Mother plants were produced from the cuttings, maintained at a temperature of 65-70° F and watered as needed by greenhouse staff. Vegetative cuttings were taken from the mother plants to obtain additional plant stock. Cuttings consisted of approximately three nodes and were treated with Hormodin 1™ (Mainland, Pennsylvania) rooting hormone prior to planting into 4” pots with vermiculite. The plants were removed from the greenhouse and placed outside to harden off in mid-May. The first round of plants were transplanted on 22-May 2018 at Borderview Research Farm in Alburgh, VT. Additional three varieties were underwent similar treatment for propagation and were transplanted 20-Jun, 2019. Approximately 14-18 individuals from each of the 11 wild hop varieties were planted totaling 184 plants overall. In the field, plants were spaced 3’ apart and planted into weed barrier fabric. Each plant was strung up on using a single coir string leading up to the top wire.

Throughout each growing season of the trial, germplasm strains were scouted for pests and diseases to observe any differences in these new strains as a means of  measuring their suitability and vigor within their native growing region. Plants were harvested using the HopHarvester and measured for total bine height, weight, cone weight, browning severity, and dry matter. Harvested hop cones were placed in drying oasts and dried overnight with wet cone subsamples of 200g taken from each hop variety. Each sample of 200g of wet hop cones was shipped to Alliance Analytical Laboratories in Coopersville, MI in the first year and to Cornell Agritech in Geneva, NY in the second year. Hops were analyzed for Brew Quality and Essential Oil tests  using American Society of Brewing Chemists (ASBC) procedures Hops 6-A, 12, 13, and 17. Quality measurements included percent moisture, hop storage index (HSI), alpha and beta acids, oil content, and volatile oil profile.

Hop Crowning Study

The replicated research plots were located at Borderview Research Farm in Alburgh, VT on a Benson rocky silt loam. The experimental design was a randomized complete block with 10’ x 35’ plots (each plot had 7 hills). Plots were replicated 3 times. Main plots consisted of two varieties. ‘Cascade’ served as a moderately resistant cultivar and ‘Nugget’ served as a downy mildew susceptible treatment. A control treatment was left with no crowning or disturbance in each year of the study. “Early” crowning treatments occurred in mid-late April depending on the early season conditions of each trial year. “Late” crowning treatments occurred as soon as hop shoots had emerged from the ground. “Late” crowning occurred in mid-May. By 2015, our studies had indicated that crowning does result in better hop yields, and that earlier crowning is more effective for this region. We hypothesized that crowning may have an effect on early season soil temperatures. Since crowning disturbs the soil while it is thawing and removes some of the surface debris that could potentially slow the warming of the earth around each hop plant, it was important to determine whether soil temperature might be contributing to better yields. The crowning experiment in 2016 tested whether early season soil temperature was an important factor in hop yield and quality. To test this, one treatment included plants that were crowned according to our standard method, one treatment included plants that were “Uncovered” to increase soil temperature without removing any hop growth. In 2017, a treatment was added to evaluate crowning plants with a flame-weeding technology. The goal was to minimize mechanical cutting that may also spread disease from plant to plant. In 2018 treatments of early crowning (27-Apr), flame-weeding (11-May), and a control were maintained. In 2019 treatments of early crowning (25-Apr), flame-weeding (10-May), and a control were maintained.  Treatments were monitored for downy mildew basal spikes and aerial spikes within each plot during the growing season.

Throughout the growing season crowning trial plots were scouted for pests and diseases to observe any differences in these treatments to measure their susceptibility, vigor, and disease incidence. Harvest of plants in each year was based on regional standards and past records using the HopHarvester. Plants from each treatment were measured for total bine height, weight, cone weight, browning severity, and dry matter. Harvested hop cones were placed in drying oasts and dried overnight with dry cone subsamples of 100g taken from each hop variety. 100g samples were taken and processed in the UVM Crops and Soils Testing Lab for alpha acids, beta acids, and HSI using ABSC approved procedures Hops 6a and Hops 12.

Hop Harvest Timing Study

Cascade hops from two Vermont farms will be collected, analyzed, and reported over the course of two growing seasons (2018 and 2019).  UVM has taken samples from Homestead Hops in Starksboro, VT and Borderview Research Farm in Alburgh, VT. Depending on the potato leafhopper, hop aphid, and spider mite populations each season, farmers may have to spray insecticide to manage these pests. On-farm hop acreage, major pest issues, pesticides used, fertility rates, fertilizers used, surrounding crops, precipitation, and cumulative growing degree days will be collected each season on all three farms. These are factors known to impact hop harvest timing. Network for Environmental and Weather Applications (NEWA) data collection stations will include Granville, NY and Alburgh, VT. The hop variety, Cascade, has been chosen for this in-depth study because it has aromatic qualities, it is a hop variety that most northeastern hop yards already have in the ground, and it is a non-proprietary hop used by local brewers.

The experimental design was split-plot replicated three times where an individual farm is a main plot and each year is a sub-plot. Three plots will be randomly selected within the Cascade hops already planted in each hop yard. Plots contained 5 hop hills (10 strings) and were marked with ground flags and flagging tape to make sure they are not harvested with the rest of the crop. There were three planned collection dates each season: Early, At Harvest, and Late. The “Early” sampling date was timed approximately 1 week prior to when planned harvest of the Cascade crop would take place. The “At Harvest” sample was taken when the Cascade harvest is normally planned. Finally, the “Late” sample was taken 1 week after harvest occurred. The “Late” sample was taken from the bines in our plots left up in the field. In addition to the three planned sample periods, we extended the research a further two weeks past the “Late” sample period in an attempt to capture potential degradation in hop cone quality.

Each sample of 200g of wet hop cones was shipped to Alliance Analytical Laboratories in Coopersville, MI overnight in the first year and then to Cornell Agritech in Geneva, NY the second year. Laboratories conducted their Brew Quality and Essential Oil tests using American Society of Brewing Chemists procedures 6-A, 12, 13, and 17. Measurements included in this test are percent moisture, hop storage index (HSI), alpha and beta acids, oil content, and volatile oil profile.

In addition to these shipped samples, samples were dried and processed for a sensory evaluation event. Blind sensory rating data will be collected at sensory evaluation workshops. Hop samples were used to brew beers for each harvest window to be evaluated in sensory workshops in conjunction with Switchback Brewers. The first workshop took place at the 11th Annual Hops Conference (28-Feb 2020).

Nitrogen Fertility Study

The experiment was conducted in 2019 and 2020. The replicated research plots were located at Borderview Research Farm in Alburgh, VT on a Benson rocky silt loam. The experimental design was a randomized complete block with 10’ x 35’ plots (each plot had 7 hills). Main plots consisted of two varieties, ‘ Centennial’ and ‘Cascade’ to represent an earlier maturing variety and later maturing variety that are in high demand amongst brewers. Plots were replicated 3 times consisting of 6 different treatments. Treatments involved four different rates of total nitrogen applied over the season with 6 unique treatments including a Control at 100#/ac applied in the spring, 150#/ac (100#/ac spring applied, 50#/ac weekly), 200#/ac (100#/ac spring applied, 100#/ac weekly), 250#/ac (100#/ac spring applied, 150#/ac weekly), 150#/ac (50#/ac spring applied, 100#/ac weekly), and 200#/ac (50#/ac spring applied, 150#/ac weekly). Weekly applications were made over an 8 week period, divided evenly over application period.

Throughout the growing season of the trial, plots were scouted for pests and diseases to observe any differences in pest pressure for each of the fertility treatments. During the growing season, petiole tests were taken on a bi-weekly basis evaluated for nitrates on-farm in addition to being sent to Dairy One in Ithaca, NY for total nitrogen analysis. Plants were harvested using the HopHarvester and measured for total bine height, weight, cone weight, browning severity, and dry matter. Whole plants were also harvested from each plot and chipped to be sent to Dairy One in Ithaca, NY for whole plant nutrient analysis.  Harvested hop cones were placed in drying oasts and dried overnight. A subsample of cones was taken for each plot and processed in the UVM NWCS Quality Testing Laboratory in Burlington, VT. Hops were analyzed for Brew Quality using American Society of Brewing Chemists (ASBC) procedures Hops 6-A, 12, 13, and 17. Measurements included in this test are percent moisture, hop storage index (HSI), alpha and beta acids. 

BENEFICIAL EXCLUSION STUDY

Within the study, we quantified naturally occurring predation and parasitism of TSSM, HA, and PLH by conducting a natural enemy exclusion experiment. The exclusion experiment was conducted at three sites (Alburgh, VT, Starksboro, VT, and Northfield, MA) three times throughout the season (June, July, and August). We used a split plot design where the treatments were “open” vs “excluded” and we replicated it across ten Nugget and ten Cascade plants at each site. We paired one “open” string and one “excluded” string per hill, and block by variety. The “excluded” treatments consisted of a single hop leaf enclosed in a 6” x 10" organza mesh bag (Uline.com) with a small piece of cotton wound around a petiole to before cinching the bag closed. The “open” treatments consisted of a single hop leaf with a small piece of cotton wound around the petiole and a twist-tie to hold it in place.

Prior to applying the treatments, we scouted 20 mature hop leaves per variety, recording the number of PLH, TSSM, and HA on each leaf. After the leaves were scouted, if any natural enemies were found they were removed. Ten leaves per variety were then assigned the “exclusion” treatment enclosed in a mesh bag and the other ten leaves per variety were assigned the “open” treatment where pests were subjected to natural enemy attack.

One week after the treatments were applied at each site, we returned, again recording the number of PLH, TSSM, and HA on each leaf (Table 1). At the end of each trial period, we compared the increase in PLH, TSSM, and HA between the “open” and “excluded” leaves for both varieties at the three sites (Image 1 & 2).

Table 1: Treatment observation dates from June-August in Northfield MA, Starksboro, and Alburgh, VT.

 

Northfield

Starksboro

Alburgh

 

Start

20-Jun

22-Jun

26-Jun

End

27-Jun

30-Jun

3-Jul

Start

21-Jul

26-Jul

25-Jul

End

28-Jul

2-Aug

1-Aug

Start

10-Aug

17-Aug

14-Aug

End

23-Aug

24-Aug

21-Aug

The three different sites, aside from being geographically distinct, are all managed slightly differently and face distinct challenges in terms of pests within their hop yards.

The Alburgh, VT location has a diverse surrounding landscape, is organic, sprayed three times for disease throughout the season, and has not been sprayed with any insecticide for three years. The Starksboro, VT location sprays insecticide occasionally and is managed conventionally. The Northfield, MA location has a comparatively less diverse surrounding habitat and is managed conventionally. The Northfield, MA location follows a more regimen schedule of pesticide applications for weeds and disease, and sprayed on a weekly basis from late-May until early-Sep. Throughout this period, three insecticide applications were made between mid-Jun and mid-Jul consisting of Imidacloprid and Bifenthrin.  

Each site within the trial had greater than average number of Growing Degree Days (GDDs) and well above average precipitation for this season, resulting in an uncharacteristically wet spring and early summer. We did generally see rain begin to normalize by the latter half of July for our southernmost locations. With different management practice we saw distinct difference in pest populations throughout the three sites.

 

Research results and discussion:

2017 and 2018 Germplasm Results

In 2017, the germplasm lines appeared to differ in their susceptibility to pests (Figure 1). Although these data were not analyzed for statistical differences, it is worth noting the observed differences in pest populations across the varieties. Two-spotted spider mites were only observed on two of the varieties while HA and PLH were present on all varieties. The variety Wolcott 001 had the highest populations of PLH averaging 2 insects per leaf while the next highest variety, Wolcott 002, averaged only 0.5 insects per leaf. The highest HA populations were observed on the variety Morris which averaged about 4.5 aphids per leaf. As we continue the study, we plan to continue to measure the impacts of these various insects on hop quality and yields, and hope to observe any variations in cultivar susceptibility.

In 2018, we also experienced adverse reactions to a combination of pesticide applications which resulted in severe plant damage to a large portion of plants. Champ was sprayed at 2 lbs ac-1 in conjunction with Regalia at 1qt ac-1 diluted in 50 gal of water.  This resulted in severe leaf and cone damage, impacting the survival of a number of the wild hops (Figure 2). While each of the wild hop varieties were adversely affected by the combination of these two fungicides, the hops growing as part of our commercial variety trials showed no phytotoxic effect. This may indicate that these hop varieties are far more susceptible to phytotoxicity caused by certain types of fungicides.

Hop varieties also differed in yield and harvest characteristics (Table 2). While all plots were harvested at similar dry matter contents, the varieties Wolcott 001 and Northfield 001 were harvested one week earlier than the others suggesting faster maturation rates. The highest yields were obtained from the variety Morris, which produced approximately 456 lbs ac-1. Although these data were not analyzed for statistical differences, it is interesting to note the observed differences in first year production across the varieties. Wolcott 001, although reaching maturity about 1 week earlier than the other varieties, produced less than 100 lbs ac-1. Varieties Wolcott 002, Kingdom 001, Kingdom 002, Northfield 003, and Peacham 002 were not harvested.

Interestingly, the varieties Morris and Mount Toby produced relatively high yields but also exhibited severe cone browning and damage. We will continue to monitor these differences as plants are monitored in future years.

Table 2.  Harvest characteristics by variety.

Variety

Total plants

Harvest date

Yield @ 8% moisture lbs ac-1

Dry matter

%

Cone Disease Severity (1-10) +

Wolcott 001

10

7-Sep

78.5

22.6

4

Argyle

6

7-Sep

207

22.4

3

Mount Toby

8

15-Sep

330

21.4

10

Northfield 001

6

15-Sep

342

21.1

2

Peacham 001

9

15-Sep

411

22.4

8

Morris

8

15-Sep

456

22.6

4

+ Cones were also rated in browning severity on a 1-10 scale where 1 indicates low browning and 10 indicates severe browning.

Hop varieties also varied dramatically in acid content and oil profiles (Table 3 and Table 4). Wolcott 001 and Argyle had similar concentrations of alpha and beta acid while Morris had significantly more alpha acid than beta acid. The opposite was true for Peacham 001 and Northfield 001. Argyle and Peacham 001 also had about double the oil content of the other varieties.

Table 3. Wild hop variety acid content.

Variety

Alpha

%

Beta

%

HSI

Northfield 001

3.60

6.70

0.249

Wolcott 001

3.80

5.00

0.280

Morris

6.00

3.40

0.241

Argyle

5.00

3.90

0.271

Peacham 001

3.00

8.60

0.264

In addition to basic quality parameters, the varieties also differed in oil profile (Table 4). Argyle and Morris produced the highest alpha levels compared to the other varieties. Peacham produced the highest beta acid levels and total oil concentrations.

Table 4. Hop aromatic oil profiles.

Variety

Oil %

b-pinene %

Myrcene %

Linalool %

Caryophyllene %

Farnesene %

Humulene %

Geraniol %

Wolcott 001

0.3

0.83

64.02

0.71

5.82

0.07

9.07

0.24

Northfield 001

0.4

0.43

41.05

0.46

5.55

0.05

18.09

0.15

Morris

0.3

0.58

46.21

0.34

5.37

0.17

15.44

0.39

Peacham 001

0.8

0.21

11.24

0.33

5.7

8.77

25.41

0.18

Mount Toby

n/a

n/a

n/a

n/a

n/a

n/a

n/a

n/a

Argyle

0.7

0.68

52.87

0.25

4.23

0.08

12.45

0.41

Table 5 summarizes the aromatic oil profiles of the harvested varieties. Each harvested variety has distinct oil compositions, which has the potential for new uses or substitutions in the brewing process. Table 5 provides a brief sensory description of individual oil characteristics.

Table 5. Oil characteristics.

Oil

Associated Scents

β-pinene

Piney, green

Myrcene

Citrus, bright, green, resinous

Linalool

Floral, orange, citrus

Caryophyllene

Woody, spicy

Farnesene

Floral, herbal

Humulene

Piney, woody, herbal, spicy

Geraniol

Floral, bright

2019 Germplasm Study Results

The germplasm lines appeared to differ in their susceptibility to pests (Figure 2). Although these data were not analyzed for statistical differences, it is worth noting the observed differences in pest populations across the varieties. With the exceptionally dry and hot summer in 2018, we noticed much higher populations of two-spotted spider mites compared to other pests. This year, Peacham 002 had the highest levels of TSSM with an average of 4.15 TSSM per leaf whereas Mount Toby had the lowest with only 0.6 TSSM per leaf. Hop Aphids (HA) and Potato Leaf Hoppers (PLH) were both observed in very low numbers throughout the ten germplasm varieties with Wolcott 001 having the highest average of HA per leaf at 0.82 and Peacham 002 at 0.35 pests per leaf for PLH. As we continue the study, we plan to continue scouting germplasm varieties on a weekly basis and hope to observe any difference in cultivar susceptibility.

In 2018, we measured the height and side arm lengths of 6 bines out of the 14 bines present in each plot (Figure 3). The length of 4 side arms on each of the 6 bines was measured. Overall, Kingdom 001 had some of the smallest plants with the lowest average plant height and side arm length. Northfield 003 and Argyle had the greatest average bine height at 4.87 m and Peacham 002 had the greatest average side arm length at 58.2 cm.

Hop varieties also differed in yield and harvest characteristics (Figure 4, Table 6). This year due to harvester constraints, the germplasm varieties had to be harvested on the same date instead of during ideal harvest periods based on aroma and dry matter. The plant yields are also for first year plants as the germplasm was once again propagated and replanted into a new hopyard. With these factors taken into consideration, Mount Toby showed highest first year yields at 370 lbs ac-1 whereas Kingdom showed the lowest yields at 71 lbs ac-1. Higher yields should be expected in subsequent years.

Table 6. 2019 Harvest characteristics by variety.

Variety

Harvest date

Yield @ 8% moisture

Harvest dry matter

Cone disease severity

 

 

lbs ac-1

%

1-10

Argyle

5-Sep

215

25.3

2

Kingdom 001

5-Sep

71.0

27.0

1

Kingdom 002

5-Sep

151

26.6

1

Morrisville 001

5-Sep

117

25.5

1

Northfield 001

5-Sep

230

26.4

2

Northfield 003

5-Sep

155

21.6

1

Peacham 001

5-Sep

219

25.1

2

Peacham 002

5-Sep

242

25.9

2

Mount Toby

5-Sep

370

24.6

3

Wolcott 001

5-Sep

232

25.4

4

Cones were also rated in browning severity on a 1-10 scale where 1 indicates low browning and 10 indicates severe browning.

In 2018, disease pressure was very low resulting in less browning throughout each of the ten harvested germplasm varieties. Despite having to harvest these wild hops at the same period, most fell within reasonable ranges if using dry matter as the sole means of determining harvest period.

Hop varieties varied dramatically in alpha and beta acids. In addition to varietal variability, hops also have potential to be influenced by various growing conditions such as fertility, temperatures, precipitation, disease pressure and many others, impacting their profiles.

Both Kingdom and Peacham samples showed some very close similarities this year in alpha and beta acids (Table 7). These two groups could be similar varieties as they were collected from similar areas, although genetic testing would need to be conducted to determine similarities or differences in the varieties.

Table 7. 2019 Wild hop variety brew quality.

Variety

Alpha

Beta

HSI

 

%

%

 

Argyle

7.90

5.50

0.36

Kingdom 001

15.9

5.50

0.30

Kingdom 002

15.1

5.10

0.28

Morrisville 001

8.80

5.90

0.28

Northfield 001

6.00

9.70

0.46

Northfield 003

3.90

7.10

0.49

Peacham 001

4.30

11.1

0.30

Peacham 002

4.90

11.2

0.16

Mount Toby

4.40

4.20

0.60

Wolcott 001

6.00

5.50

0.40

This year we were also forced to switch labs, adding another variable into the equation making it difficult to compare between years as processes differed slightly. In addition to the switch, samples molded while in possession of Alliance Analytical and samples were not able to be run accurately for essential oil profiles.

In addition to lab difficulties, hops had to all be harvested at the same time in 2018. In 2017, Wolcott 001 and Argyle were harvested on 7-Sep, whereas Northfield 001, Morrisville 001, and Peacham 001 were all harvested a week later on 15-Sep. In 2018, all varieties were harvested on 5-Sep. In 2018, the hot and dry conditions from the season could have impacted the resin and oil profiles in addition to our necessity to harvest plants early this season. There is the potential that cones did not have the chance to fully develop resins or fully develop their essential oil profiles as a result of growing conditions or other circumstances. While we were able to have these samples analyzed for brew quality, samples did not have the chance to be accurately analyzed for essential oils and we were not able to compare these varieties with last years results.

2017 Crowning Study Results

Table 8. Temperature, precipitation from 2017.

2017

March

April

May

June

July

August

Sept

Average temperature (°F)

25.1

47.2

55.7

65.4

68.7

67.7

64.4

Departure from normal

-6.05

2.37

-0.75

-0.39

-1.90

-1.07

3.76

 

 

 

 

 

 

 

 

Precipitation (inches)

1.6

5.2

4.1

5.6

4.9

5.5

1.8

Departure from normal

-0.63

2.40

0.68

1.95

0.73

1.63

-1.80

 

 

 

 

 

 

 

 

Growing Degree Days (base 50°F)

7

111

245

468

580

553

447

Departure from normal

7

111

47

-7

-60

-28

129

In the 2017 growing season there were an accumulated 2411 Growing Degree Days (GDDs) this season, approximately 199 more than the historical 30-year average (Table 8). 2017 proved to be the wettest year throughout our five year study putting hops at a much higher risk for disease infection for a large portion of the growing season. During critical growth and development periods we experienced rain events averaging 7.39 inches above our 30-year averages despite having late summer months that began to taper off.

Table 9. Temperature, precipitation from 2018.

2018

March

April

May

June

July

August

Sept

Average temperature (°F)

30.4

39.2

59.5

64.4

74.1

72.8

63.4

Departure from normal

-0.66

-5.58

3.1

-1.38

3.51

3.96

2.76

 

 

 

 

 

 

 

 

Precipitation (inches)

1.5

4.4

1.9

3.7

2.4

3

3.5

Departure from normal

-0.7

1.61

-1.51

0.05

-1.72

-0.95

-0.16

 

 

 

 

 

 

 

 

Growing Degree Days (base 50°F)

1

37

352

447

728

696

427

Departure from normal

1

37

154

-27

88

115

109

In the 2018 growing season there were an accumulated 2688 Growing Degree Days, 477 more than the historical 30-year average. 2018 was unusually hot and dry accumulating far less rain during the bulk of the growing season (May-Sep) than the average year. Hot and dry conditions impacted disease pressure and yields (Table 9).

2017

In 2017 we experienced well above normal precipitation which lead to very high disease pressure and incidence within the hop yard. Within this wet season, we continued to notice trends on the significant impact of crowning on cone weights, in addition to some less significant impacts on yield and cone disease severity (Table 10). Yield and cone weights were consistently impacted by crowning throughout the study to some effect, whereas other metrics may be influenced by growing conditions. Because of the wet season and high disease pressure, our sample size was significantly reduced and individual plants were analyzed within plot treatments as opposed to entire replicated plots, which could have potentially had an impact on results for the year.

Table 10 : 2017 Dry matter, yield, 100 cone weight, cone disease incidence, cone disease severity.

Treatment

Dry Matter

Yield @ 8% moisture

100 Cone Weight

Cone Disease Incidence

Cone Disease Severity

%

lbs ac-1

g

%

1-5

Control

23.3

1073

13.8

86.4

2.95

Crowned Early

24.1

1308

15.8

88.8

2.50

Flamed

n/a

n/a

n/a

n/a

n/a

Trial mean

23.6

1161

14.5

87.3

2.78

p-value

0.296

0.155

0.089

0.454

0.120

*Treatments with an asterisk are not significantly different than the top performer in bold.

 

Table 11 : 2018 Dry matter, yield, 100 cone weight, cone disease incidence, cone disease severity.

Treatment

Dry Matter

Yields @ 8% moisture

100 Cone Weight

Cone Disease Incidence

Cone Disease Severity

%

lbs ac-1

g

%

1-5

Control

24.8

642*

14.2

63.7

2.00

Crowned Early

25.1

584

13.0*

70.3

2.00

Flamed

24.6

786

11.4

73.3

1.50

Trial mean

24.8

671

12.9

69.1

1.83

LSD

NS

189

2.36

NS

NS

*Treatments with an asterisk are not significantly different than the top performer in bold.

 The flamed treatment, 11-May, yielded highest. While there was not a significant difference in yield between crowning and control treatments this year, crowning did have the lowest yield compared to control and flamed treatments. Flaming resulted in significantly smaller cone sizing on hop plants despite having highest yields in the 2018 trial (Table 11). 

HARVEST TIMING

Table 12 shows a summary of the temperature, precipitation and growing degree day (GDD) summary. The 2017 growing season in Northfield, MA was fairly similar to Vermont growing conditions accumulating 2255 GDDs this season, 43 more than the historical 30-year average. Precipitation for the early part of the growing season was well above normal averages especially in May, where they experienced over 3” of rain above average.

Table 12. Temperature, precipitation and growing degree day summary. Northfield, MA, 2017.

2017 Northfield, MA

March

April

May

June

July

August

Sept

Average temperature (°F)

29.7

49

54.8

65.4

69.1

67.1

64.5

Departure from normal

1.45

-4.17

1.65

0.39

1.5

1.67

-3.86

 

 

 

 

 

 

 

 

Precipitation (inches)

2.52

3.18

6.52

4.64

2.5

4.3

2.42

Departure from normal

0.29

0.38

3.1

0.99

-1.67

0.43

-1.18

 

 

 

 

 

 

 

 

Growing Degree Days (base 50°F)

4

99

164

461

588

515

424

Departure from normal

4

99

-34

-14

-52

-66

106

 

Table 13 provides a summary of the analyzed oil characteristics and the aromatic qualities that they may contribute during the brewing process.

Table 13. Oil characteristics.

Oil

Associated Scents

β-pinene

Piney, green

Myrcene

Citrus, bright, green, resinous

Linalool

Floral, orange, citrus

Caryophyllene

Woody, spicy

Farnesene

Floral, herbal

Humulene

Piney, woody, herbal, spicy

Geraniol

Floral, bright

Harvest periods were broken down into early, normal, and late periods. The early period for Cascade was taken from 14-Aug through 21-Aug, normal harvest period is taken from 25-Aug through 5-Sep, and late harvest period is taken from 8-Sep through 18-Sep. Total analyzed oils for Cascade generally increased from early to late harvest periods, peaking during the late harvest period (Figure 3). The largest component was made up of myrcene which peaked during the normal harvest period and stayed relatively consistent through late harvest, as did caryophyllene. Whereas humulene and farnesene steadily increased as time went by. Cascade Alpha acids were consistent throughout the harvest and beta acids peaked slightly during the normal time period (Figure 4).  

The early period for Magnum was taken from 14-Aug through 21-Aug, normal harvest period was taken from 25-Aug through 5-Sep, and late harvest period was taken from 8-Sep through 18-Sep. Total analyzed oils for Magnum generally increased from early to late harvest periods, peaking during the late harvest period (Figure 5). As with Cascade, the largest component of the oil profile was made up of myrcene. In Magnum the myrcene and caryophyllene levels steadily increased as time went by, whereas humulene peaked in the normal harvest period. Magnum resin levels were relatively consistent, with a slight drop off for beta acids during the late harvest period (Figure 6).

The early period for Nugget was taken from 18-Aug through 28-Aug, normal harvest period was taken from 1-Sep through 11-Sep, and late harvest period was taken from 15-Sep through 22-Sep. Total analyzed oils increased over time peaking during the late harvest period (Figure 7). Myrcene showed a noticeable increase over the harvest period whereas humulene peaked during the normal harvest period for Nugget. Resins for Nugget had increasing levels over the tested period and peaked during the late harvest window (Figure 8).

The early period for Centennial was taken from 11-Aug through 18-Aug, normal harvest period was taken from 21-Aug through 28-Aug, and late harvest period was taken from 1-Sep through 8-Sep. Total analyzed oils for Centennial were highest during the early period and showed fluctuations throughout harvest periods (Figure 9). Resins showed similar fluctuations with peak concentrations of alpha and beta acids during the early harvest period (Figure 10).

The early period for Crystal was taken from 21-Aug through 1-Sep, normal harvest period was taken from 5-Sep through 15-Sep, and late harvest period was taken from 18-Sep through 29-Sep. Total analyzed oils increased over time once peaking during the late harvest period. While myrcene continued to develop over time and peaked with the total oils, humulene, caryophyllene and geraniol were highest during the early harvest period (Figure 11). While beta acids remained fairly consistent across harvest periods, alpha acids appear to have peaked in the late harvest period (Figure 12).

2018 Hop Harvest Timing Results

In 2018, we were required to switch labs for hop analysis. In past experiments, Alpha Analytics in Yakima, WA conducted hop oil analysis. Unfortunately, this lab stopped accepting samples in 2018. Hence, we were required to find another lab with the ability to test for essential oils and resins. The lab chosen for the project was Alliance Analytical Laboratories located in Coopersville, MI. Samples were shipped directly to the company and handling was unfortunately inadequate and led to samples becoming moldy. We were able to receive results for brew quality as this test was conducted prior to sample degradation.

Alpha acid, beta acid, cohumulone, colupulone, HIS, and moisture were measured for each harvest date (Table 14). Moisture was variable across all five samples and there was no significant difference between each of the harvest dates. While no statistical difference was noted between Early, Normal, and Late harvest dates, each date would have been deemed “ready to harvest” if using moisture as the sole means of determining harvest timing. Harvesting before aromas fully develop can result in lesser quality hops, making it important to use additional means of measuring hop readiness to determine ideal harvest windows.

Cohumulone makes up a large percentage of total alpha acids and contributes to the bittering qualities of the hops after isomerization in the brewing process. Colupulone makes up a large percentage of total beta acids and would thus contribute largely to hop aromatics and later bitterness in beers after oxidization and conversion to hulupone. Cohumulone and colupulone are presented as a percentage of alpha and beta acids respectively. Cohumulone was highest in HD 4 and HD 3. Colupulone was highest in HD 3 with statistically similar levels shown in HD 4, HD 5, and HD 2.

Table 14. Brewing quality for Cascade hops harvested over a 5 week period in 2018.

Harvest Date

Alpha acid

Beta acid

Cohumulone

Colupulone

HSI

Moisture

%

%

% relative to alpha

% relative to beta

 

%

HD 1

4.2

5.6

29.8

47.2

0.22

65.47

HD 2

5.0

6.2

30.0

49.7*

0.09*

76.33

HD 3

7.0*

7.4*

32.0*

50.3

0.04

64.27

HD 4

6.9*

7.1*

32.0

50.1*

0.53

73.07

HD 5

7.6

8.5

31.4

49.6*

0.12*

74.87

LSD (0.10)

2.0

2.1

0.46

0.86

0.13

NS

Trial mean

6.1

6.9

31.0

49.4

0.20

70.8

* Treatments with an asterisk are not significantly different than the top performer in bold.

 

LSD - Least significant difference. NS – no significant difference.

 

               

 

Normal and Late harvest dates (HD 3, HD 4, and HD 5) had the highest percentage of alpha and beta acids compared to the earlier harvest dates (Figure 15 and 16). Major jumps in both alpha and beta acids occurred after Early harvest dates (HD 1 and HD 2). HD 3, HD 4, and HD 5 had the highest values for brewing qualities.

HSI measures the potential loss of alpha and beta acid over time; a lower number for HSI means less potential for loss. HSI can also be an indicator of handling and storage practices as the degradation of alpha and beta acids can be accelerated by increased temperatures, exposure to air, and exposure to light. Values for HSI less than 0.40 are generally acceptable but lower values below 0.30 are ideal. Our Normal harvest period (HD 3) also had the lowest HSI showing that resins would be most stable over time for this harvest date (Figure 17). The sample from HD 4 had the highest HSI and would be most subject to alpha and beta acid degradation. This sample may have been subject to improper handling. As a whole, Normal and Late harvest dates were all top performers in the trial and exhibited highest values for alpha acid, beta acid, cohumulone, and colupulone. Again due to laboratory error we were unable to test for changes in the hop oil profiles.

BENEFICIAL EXCLUSION STUDY

The open treatment would have allowed for natural enemies to prey on the hop pest populations whereas the excluded treatment would have kept natural predators away from the pests. Hence, it is expected that a decrease in pests in the open treatment would be a sign of predation due to populations of natural predators. An increase in pests in the open treatment may indicate an absence or low abundance of natural predators.

The Northfield, MA site showed very few significant differences in pest counts between open and excluded treatments for any of the sampling periods. There was a significant difference observed between open and excluded treatments for TSSM in June. There was an increase of 23.3 TSSM in the open treatment, whereas the exclusion treatment showed an increase of 6.40 (Figure 13).

In Starksboro there was no difference in TSSM counts for open and excluded treatments throughout the entire season, but there were some differences in June PLH and August HA counts. For June, there was an increase of 1.80 PLH in the open treatment and an increase of 5.20 for excluded treatment (Figure 14). The HA also showed significant differences in August with an increase of 1.20 for the open treatment, and an increase of 7.95 for excluded treatment (Figure 15).

The Alburgh site showed the most significant differences in pest counts when leaves were left open or excluded. In June there was a difference in TSSM, though very small, showing and increase of 0.25 for open treatments and a decrease of 0.20 for excluded treatments. In July, the HA showed a 4.10 increase for open and an 18.2 increase for the excluded treatment (Figure 16). In August we saw differences in both HA and TSSM. The HA had an increase of 2.35 for the open treatment whereas the excluded treatment had an increase of 49.1 (Figure 17). For TSSM there was an increase of 0.05 for the open treatment and an increase of 2.83 for the excluded treatment (Figure 18).

2019 & 2020 Hop Fertility Results

Within the trial, fertility rates appeared to have little to no impact on observed pests with the exceptions of hop aphids (Table 15). Aerial spikes were observed throughout the study yet fertility treatments appeared to have no impact on spike incidence when looking at nitrogen treatments alone. In general, hop aphids appeared to be present in much larger populations in 2019 compared to past years as a result of weather conditions favorable to aphids. The highest average population populations were observed on one of the higher nitrogen application treatments, 100_100 lbs N ac-1 with an average of 6.65 aphids leaf-1 compared to lowest populations observed on the 100_50 lbs N ac-1  treatment at 2.17 aphids leaf-1 and a trial average of 3.59 aphids leaf-1. That being said there were also some “hot pockets” within the hop yard in which with some single leaf populations exceeded 100 aphids leaf-1 and a number of weekly scouting populations exceeding some proposed action thresholds of 5-10 aphids leaf-1.

Table 15. Average insect pest and disease scouting incidence for nitrogen fertility rates, Alburgh, VT 2019.

Treatment Spring_Summer lbs N ac-1

Total applied N

Aerial spikes

Basal spikes

HA

PLH

TSSM

 

plot-1

plot-1 

leaf-1

leaf-1 

leaf-1 

100

100

0.471

1.16

3.52 a†

2.32

1.18

100_50

150

0.395

1.04

2.17 b

2.32

0.757

50_100

150

0.326

0.692

3.03 ab

2.68

1.05

100_100

200

0.214

0.946

6.65 a

2.72

1.02

50_150

200

0.400

0.754

2.70 b

2.58

0.479

100_150

250

0.414

0.821

3.46 ab

2.69

0.146

LSD (0.10)‡

 

NS¥

NS

3.70

NS

NS

Trial mean

 

0.370

0.901

3.59

2.55

0.772

†Within a column treatments marked with the same letter were statistically similar (p=0.10). Top performers are in bold.

‡LSD –Least significant difference at p=0.10.

¥NS –No significant difference between treatments

Throughout the growing period, plots were sampled every other week for leaf petiole nitrates from 13-Jun to 31-Jul (Table 16). Collected petiole samples were analyzed on-farm for nitrates and sent out for total nitrogen. Basic guidelines have been proposed for determining plant nitrogen requirements yet there are no current recommendations based on these in-field nitrate readings. Collected leaf petiole samples may fall into three categories including Low: 0-6000ppm, Normal: 6000-10,000ppm, and High: 10,000+ppm.

Throughout the sampling period (2-Jul through 31-Jul), treatment differences between petiole nitrates were significant within the 16-Jul and 31-Jul sampling dates. Most notably the 100 lbs N ac-1 treatment (lowest in the study) was significantly lower than the other treatments in these two dates, whereas those receiving a minimum 50 lbs N ac-1 extra, were sustaining similar levels of petiole nitrates. Overall nitrate levels followed decreasing trends over the course of the sampling period with highest values observed in 200 and 250 lbs N ac-1 treatments.

Total percent N followed similar trends over time, but some more consistent differences were observed between application rates. The 250 lbs N ac-1 treatments was consistently the highest percentage total nitrogen and the 100 lbs N ac-1 treatment was consistently the lowest percent total nitrogen. While the differences were slight between equal total nitrogen treatments (at the 150 and 200 lb rates), those receiving higher summer application totals appeared to have slightly higher total nitrogen within petioles. Application rates over 200 lbs N ac-1 did not further increase % N concentrations in the petioles.

Table 16. Leaf petiole nitrates and total nitrogen over sampling period, Alburgh, VT, 2019.

Treatment Spring_Summer lbs N ac-1

Total applied N

2-Jul

16-Jul

31-Jul

13-Jun

2-Jul

16-Jul

31-Jul

lbs ac-1

ppm NO3-

ppm NO3-

ppm NO3-

%

%

%

%

100

100

7550

6213 b †

4125 b

3.76 b

2.97 c

1.86 d

1.41 d

100_50

150

8400

7363 a

5963 a

3.86 b

3.19 b

2.16 c

1.55 cd

50_100

150

7550

7100 a

5988 a

3.87 b

3.22 ab

2.22 bc

1.66 bc

100_100

200

8963

7888 a

5900 a

3.99 ab

3.33 ab

2.35 ab

1.80 ab

50_150

200

9338

7688 a

6088 a

4.17 a

3.34 ab

2.44 a

1.83 a

100_150

250

8975

7625 a

6325 a

4.18 a

3.37 a

2.45 a

1.92 a

LSD (0.10)

 

 NS ¥

 851

806 

 0.296

0.159 

0.171 

0.156

Trial Mean

 

8463

7313

5731

3.97

3.24

2.25

1.70

†Within a column treatments marked with the same letter were statistically similar (p=0.10). Top performers are in bold.

‡LSD –Least significant difference at p=0.10.

¥NS –No significant difference between treatments

 

Whole bines were processed for nutrient analysis (Table 17). There was a significant difference across treatments for percent N, potassium, phosphorus, magnesium, manganese, iron, and zinc. Nitrogen, magnesium and manganese all showed increasing plant concentration trends with increased N rates from 100 lbs N ac-1 to 250 N ac-1. Peak whole plant N and magnesium concentrations were observed at the highest 250 N ac-1 rate whereas manganese concentrations peaked at the 200 N ac-1 rate (50_100 N ac-1 treatment). Conversely, phosphorus and potassium showed peak values at lower N application rates and lower concentrations at higher N application rates. In most cases nutrient concentrations were maximized at 150 lbs N ac-1.  A number of these factors may have been impacted by soil available nutrients as well as changes in pH that may have resulted from the increasing rate of fertilizer within the trial. Nitrogen management of soil is closely linked to the plant uptake of a wide number of nutrients. The trial results indicated that application of N can help to improve the availability and subsequent uptake of other essential nutrients.

  Table 17. Whole plant nutrients at harvest, Alburgh, VT, 2019

Treatment Spring_Summer lbs N ac-1

Total applied N

Nitrogen

Potassium

Phosphorus

Calcium

Magnesium

Manganese

Iron

Copper

Boron

Zinc

 

%

%

%

%

%

ppm

ppm

ppm

ppm

ppm

100

100

2.02 c †

1.60 a

0.382 ab

2.40

0.378 b

58.5 b

94.4 b

82.9

37.1

17.9 b

100_50

150

2.10 bc

1.59 ab

0.393 a

2.49

0.423 ab

66.3 b

106 ab

71.8

41.5

25.0 ab

50_100

150

2.17abc

1.58 ab

0.375 ab

2.47

0.406 ab

77.0 ab

152 ab

69.4

39.2

30.5 a

100_100

200

2.26 ab

1.54 ab

0.361 abc

2.58

0.434 ab

91.5 a

122 ab

77.9

37.5

23.7 ab

50_150

200

2.30 ab

1.61 a

0.347 bc

2.40

0.431 ab

97.8 a

283 a

72.6

39.8

23.7 ab

100_150

250

2.38 a

1.49 b

0.338 c

2.62

0.467 a

92.8 a

103 ab

75.3

40.3

21.6 ab

LSD (0.10)

 

 0.221

0.102 

 0.039

NS  ¥

0.069 

24.4 

 182

 NS

 NS

 9.73

Trial mean

 

2.20

1.57

0.366

2.49

0.423

80.6

143

75.0

39.2

23.7

†Within a column treatments marked with the same letter were statistically similar (p=0.10). Top performers are in bold.

‡LSD –Least significant difference at p=0.10.

¥NS –No significant difference between treatments

 

At harvest 100 cone weight, diseased cone percentages, disease severity, harvest dry matter, and yields were recorded (Table 18). There was no difference across treatments for 100 cone weights or yields, however there were significant differences in the percentage of diseased cones, disease severity, and harvest dry matter. Disease was least prevalent in the 100_100 lbs N ac-1 (200 lbs total N ac-1) treatment at 54.5% and with a relatively low disease severity rating at 2.63. It also appeared that, with equal total nitrogen application rates, higher amounts of nitrogen applied in the summer months during the vegetative period may increase chance of disease and the severity. This can be seen specifically when comparing the 200 lbs N ac-1   treatments with lowest severity in the 100_100 lbs N ac-1 treatment and highest severity in the 50_100 lbs N ac-1 treatment. Yields did not appear to be impacted by fertility rates within the trial for this growing seasons conditions, but highest yield was observed with the 100_150 lbs N ac-1 treatment with a trial average of 901 lbs ac-1.

Table 18. Fertility trial yields and cone quality, Alburgh, VT 2019.

Treatment Spring_Summer lbs N ac-1

Total applied N

100 cone weight

Diseased cones

Disease severity

Harvest dry matter

Yield at 8% moisture

 

g

%

1-10 

%

lbs ac-1

100

100

50.8

68.3 b †

3.38 ab

24.3 abc

973

100_50

150

46

65.4 b

3.13 ab

25.0 a

820

50_100

150

46.8

68.0 b

3.25 ab

24.8 ab

911

100_100

200

48.2

54.5 a

2.63 a

23.4 c

812

50_150

200

50.8

62.8 ab

3.75 b

25.0 a

1000

100_150

250

50.5

67.8 b

3.00 ab

23.6 bc

888

LSD (0.10)

 

NS 

 9.75

 1.06

1.26 

NS ¥

Trial mean

 

48.8

64.4

3.19

24.4

901

†Within a column treatments marked with the same letter were statistically similar (p=0.10). Top performers are in bold.

‡LSD –Least significant difference at p=0.10.

¥NS –No significant difference between treatments

Cones were rated in browning severity on a 1-10 scale where 1 indicates low browning and 10 indicates severe browning.

Higher rates of nitrogen also appeared to have some impact on hop resins (Table 19). Highest values for both alpha and beta acids were seen at the lowest nitrogen rate with 8.90% alpha acid and 3.62% beta acid. The lowest values were observed that the highest nitrogen rate at 7.37% alpha acid and 2.98% beta acid. It should be noted that alpha and beta acids did not differ statistically between 100 and 150 lbs N ac-1 application rate. Essentially indicating that rates over 200 lbs N ac-1 might actually depress quality of the hops. The various nitrogen application rates appeared to have no impact on hop storage index (HSI).

Table 19. Fertility trial brew quality, Alburgh, VT, 2019.

Treatment Spring_Summer lbs N ac-1

Total applied N

Alpha acids

Beta acids

HSI

   

%

%

 

100

100

8.90 a

3.62 a

0.257

100_50

150

8.31 ab

3.43 ab

0.256

50_100

150

8.09 abc

3.12 ab

0.224

100_100

200

8.21 abc

3.23 ab

0.235

50_150

200

7.66 bc

3.08 bc

0.229

100_150

250

7.37 c

2.98 c

0.231

LSD (0.10)

 

0.921

0.398

NS ¥

Trial mean

 

8.09

3.24

0.239

†Within a column treatments marked with the same letter were statistically similar (p=0.10). Top performers are in bold.

‡LSD –Least significant difference at p=0.10.

¥NS –No significant difference between treatments.

Table 20 shows a summary of the temperature, precipitation and growing degree-day (GDD) summary. In the 2020 growing season, there were an accumulated 2544 GDDs, 66 more than the historical 30-year average with greatest deviations from the norm occurring in July, 121 GDD’s above average. The 2020 growing season experienced a dry summer with well below average precipitation occurring during the months of May and June. Supplemental irrigation was applied to plants at a rate of 4500 gal ac-1, however drier summer months and limited well capacity resulted limited the ability to provide adequate water to the crop.

Table 20. Temperature, precipitation and growing degree day summary, Alburgh, VT, 2020.

Alburgh, VT

March

April

May

June

July

August

Sept

Average temperature (°F)

35.0

41.6

56.1

66.9

74.8

68.8

59.2

Departure from normal

3.94

-3.19

-0.44

1.08

4.17

0.01

-1.33

 

 

 

 

 

 

 

 

Precipitation (inches)

2.79

2.09

2.35

1.86

3.94

6.77

2.75

Departure from normal

0.57

-0.72

-1.04

-1.77

-0.28

2.86

-0.91

 

 

 

 

 

 

 

 

Growing Degree Days (50-86°F)

16

44

298

516

751

584

336

Departure from normal

-6

-67

6

35

121

2

-24

Based on weather data from a Davis Instruments Vantage Pro2 with WeatherLink data logger. Historical averages are for 30 years of NOAA data (1981-2010) from Burlington, VT. (http://www.nrcc.cornell.edu/page_nowdata.html).

Pest and disease

Within the trial, fertility rates appeared to have little to no impact on observed pests with the exceptions of hop aphids in the Centennial variety (Table 21). No treatment differences were observed for the Cascade variety for pests. Hop aphid populations were highest in the 50/150 lbs N ac-1 treatment at 3.06 aphids per leaf. All N rates either higher or lower had significantly lower HA compared to the 50/150 N treatment rate.  The two-spotted spider mite (TSSM) and potato leaf hopper (PLH) populations were not impacted by the fertility treatments. In general, populations of HA were lower than previous years and much higher levels of TSSM populations. Populations of TSSM peaked in the hundreds per leaf prior to miticide application in the summer largely as a result of ideal hot and dry conditions conducive to TSSM outbreaks. Weekly basal and aerial downy mildew spikes developing during the scouting period were not impacted by fertility treatments for either variety.

Table 21. Average insect pest and disease scouting incidence for nitrogen fertility rates on Centennial hops, Alburgh, VT, 2020.

Treatment Spring/Summer

Total applied N

Basal spike

Aerial spike

TSSM

PLH

HA

lbs N ac-1 

lbs N ac-1 

plot-1 

plot-1 

leaf-1 

leaf-1 

leaf-1 

100

100

0.261

1.25

15.2

5.26

1.13

b†

100/50

150

0.875

0.667

12.4

4.79

1.64

b

50/100

150

0.300

0.333

13.4

4.24

1.56

b

100/100

200

0.458

0.083

9.98

3.60

1.34

b

50/150

200

0.463

0.667

13.2

5.28

3.06

a

100/150

250

0.521

0.250

14.1

5.37

1.69

b

LSD (0.10) ‡

 

NS ¥

NS

NS

NS

1.23

 

Variety Mean

 

0.480

0.542

13.0

4.76

1.74

 

HA= hop aphid. PLH = Potato leaf hopper. TSSM = two-spotted spider mites.

†Within a column treatments marked with the same letter were statistically similar (p=0.10). Top performers are in bold.

‡LSD –Least significant difference at p=0.10.

¥NS –No significant difference between treatments.

 

Tissue analysis

Whole bines were processed for nutrient analysis (Tables 22 & 23). For the Cascade variety, N rate treatments were statistically different in phosphorus, manganese, and iron concentrations across treatments. For Centennial, treatment differences were observed in nitrogen, potassium, phosphorus, calcium, manganese, and iron. Highest nitrogen and manganese concentrations were observed in the 100/150 lbs N ac-1 treatment for Centennial at 2.44% and 72.8ppm respectively. Total plant nitrogen decreased with each tier of down to the lowest value observed at 2.01% for the 100 lbs N ac-1 treatment with manganese following some similar general trends. Other macronutrients such as potassium and phosphorus were highest in the Centennial hops at the lowest Nitrogen application rates whereas others showed peak tissue concentrations for mid-range total nitrogen treatments such as iron and calcium. Cascade hops appeared to have a visible decline in plant growth and quality from year two to year three (2020). This became much more apparent as normal side arm initiation occurred in the Centennial hops and the Cascade hops failed to develop side arms with much smaller hop clusters borne directly from the main bines. Nitrogen management of soil is closely linked to the plant uptake of a wide number of nutrients. The trial results (specifically for the Centennial variety) indicated that application of N can help to improve the availability and subsequent uptake of other essential nutrients, but highest rates may reduce the uptake of some.

Table 22. Cascade whole plant nutrient analysis at harvest, Alburgh, VT, 2020.

Treatment Spring/Summer

Nitrogen

Potassium

Phosphorus

Calcium

Magnesium

Manganese

Iron

Copper

Boron

Zinc

lbs N ac-1

 %

%

%

%

%

ppm

ppm

ppm

ppm

ppm

100

2.06

1.52

0.458

a

2.04

0.403

57.5

ab

74.1

b

81.1

37.9

23.5

100/50

2.05

1.40

0.407

ab†

2.02

0.430

60.5

ab

75.1

ab

61.3

37.1

24.5

50/100

2.02

1.43

0.417

ab

2.00

0.397

53.0

b

78.0

ab

73.1

36.5

23.8

100/100

2.00

1.48

0.421

ab

2.02

0.391

65.5

a

85.7

ab

81.2

38.7

26.9

50/150

2.11

1.45

0.398

b

2.07

0.426

65.3

a

86.5

ab

70.4

38.2

24.2

100/150

2.06

1.38

0.406

ab

2.05

0.415

63.8

ab

123

a

75.8

38.2

23.8

LSD (0.10) ‡

NS¥

NS

0.057

 

NS

NS

11.5

 

48.8

 

NS

NS

NS

Variety Mean

2.05

1.44

0.418

 

2.03

0.410

60.9

 

87.1

 

73.8

37.8

24.4

†Within a column treatments marked with the same letter were statistically similar (p=0.10). Top performers are in bold.

‡LSD –Least significant difference at p=0.10.

¥NS –No significant difference between treatments

 

Table 23. Centennial whole plant nutrient analysis at harvest, Alburgh, VT, 2020.

Treatment Spring/

Summer

Nitrogen

Potassium

Phosphorus

Calcium

Magnesium

Manganese

Iron

Copper

Boron

Zinc

 

lbs N ac-1

%

%

%

%

%

ppm

ppm

ppm

ppm

ppm

 

100

2.01

c

1.56

a

0.468

a

2.03

b

0.385

45.3

d

91.3

ab

99.1

32.6

23.8

100/50

2.12

bc

1.49

ab

0.374

b†

2.11

ab

0.385

54.0

bcd

70.1

b

86.2

28.7

22.4

50/100

2.15

bc

1.49

ab

0.390

b

2.15

ab

0.392

47.8

dc

219

a

91.6

31.4

24.6

100/100

2.26

ab

1.34

b

0.342

b

2.26

a

0.410

63.8

abc

81.1

ab

105

30.1

22.1

50/150

2.27

ab

1.43

ab

0.348

b

2.03

b

0.402

65.3

ab

70.4

b

82.9

28.6

20.9

100/150

2.44

a

1.47

ab

0.344

b

2.19

ab

0.405

72.8

a

73.4

b

79.8

29.4

22.2

LSD (0.10) ‡

0.209

 

0.170

 

0.058

 

0.210

 

NS¥

16.1

 

145

 

NS

NS

NS

 

Variety Mean

2.21

 

1.46

 

0.378

 

2.13

 

0.396

58.1

 

101

 

90.7

30.1

22.7

 

                                             

†Within a column treatments marked with the same letter were statistically similar (p=0.10). Top performers are in bold.

‡LSD –Least significant difference at p=0.10.

¥NS –No significant difference between treatments

 

Yields and cone quality

At harvest, 100 cone weight, diseased cone percentages, disease severity, harvest dry matter, and yields were recorded (Table 24 and 25). For both the Cascade and Centennial hops, there was no difference across treatments for bine weight or 100 cone weights within variety. For the Cascade hops, significant differences were only observed in the percentage of diseased cones with the highest percentage observed (79.3%) in the 100/50 lbs N ac-1 treatment. It’s also worth noting that, overall, the percentage of diseased cones for the Cascade hops (69.5% average) was much higher than the Centennial average (29.9% average) in addition to greater disease severity by 1.67 points on the given 1-10 scale. More treatment differences were observed within the Centennial hops including diseased cones, disease severity, harvest dry matter, and yields (Table 25). Within the variety, harvest dry matter was highest for the 50/150 lbs N ac-1 treatment though was statistically similar to all other treatments receiving summer applied nitrogen applications. Similarly, highest yields in the Centennial hops were seen in the 50/150 lbs N ac-1 treatment and was statistically similar to the 100/50, 50/100, and 100/100 lbs N ac-1 treatments.

Table 24. Cascade yields and cone quality, Alburgh, VT 2020.

Treatment Spring/Summer

Total applied N

Bine weight

100 cone weight

Diseased cones

Disease severity

Harvest dry matter

Yield at 8% moisture

lbs N ac-1

lbs N ac-1

lbs

g

%

1-10

%

lbs ac-1 

100

100

2.58

32.1

65.3

ab

2.75

21.7

300

100/50

150

2.76

29.2

79.3

a

2.75

21.6

329

50/100

150

2.65

29.0

59.8

b

3.00

22.9

316

100/100

200

3.36

29.2

70.3

ab†

3.00

21.6

363

50/150

200

3.24

27.6

70.8

ab

2.75

21.8

267

100/150

250

3.16

30.7

71.8

ab

3.75

22.4

336

LSD (0.10) ‡

 

NS ¥

NS

16.0

 

NS

NS

NS

Variety Mean

 

2.96

29.6

69.5

 

3.00

22.0

319

†Within a column treatments marked with the same letter were statistically similar (p=0.10). Top performers are in bold.

‡LSD –Least significant difference at p=0.10.

¥NS –No significant difference between treatments

Cones were rated in browning severity on a 1-10 scale where 1 indicates low browning and 10 indicates severe browning.

Table 25. Centennial yields and cone quality, Alburgh, VT 2020.

Treatment Spring/Summer

Total applied N

Bine weight

100 cone weight

Diseased cones

Disease severity

Harvest dry matter

Yield at 8% moisture

lbs N ac-1

lbs N ac-1

lbs

g

%

1-10

%

lbs ac-1

100

100

2.49

38.9

27.0

ab

1.25

b†

20.6

b

438

b

100/50

150

3.56

40.7

33.5

a

1.25

b

21.7

ab

542

ab

50/100

150

3.48

41.5

32.0

ab

1.25

b

21.7

ab

510

ab

100/100

200

3.11

39.5

25.8

b

1.00

b

21.0

ab

496

ab

50/150

200

3.24

43.6

32.5

a

2.00

a

21.9

a

604

a

100/150

250

2.89

38.7

28.5

ab

1.25

b

21.3

ab

482

b

LSD (0.10) ‡

 

NS ¥

NS

6.59

 

0.64

 

1.20

 

109

 

Variety Mean

 

3.13

40.5

29.9

 

1.33

 

21.4

 

512

 

                           

†Within a column treatments marked with the same letter were statistically similar (p=0.10). Top performers are in bold.

‡LSD –Least significant difference at p=0.10.

¥NS –No significant difference between treatments

Cones were rated in browning severity on a 1-10 scale where 1 indicates low browning and 10 indicates severe browning.

Brew quality

Higher rates of nitrogen appeared to have a negative impact on the brew quality of the Cascade cones for hop storage index (HIS) (Table 26). Values below 0.300 for HSI are considered to be of good quality with those reaching higher values above 0.400 becoming of questionable or poor quality. Highest observed values for HSI were seen at the 100/100 lbs N ac-1 treatment at 0.639 (poor quality) compared and was statistically similar to all other treatments receiving summer nitrogen with the lowest value observed in the 100 lbs N ac-1 treatment at 0.212. Beta acids were lowest at the 100/150 lbs N ac-1 treatment (250 lbs N total) at 1.87%. While differences in alpha acids were not significantly different, there are some observable differences between the highest nitrogen rates which were around 4% alpha acids and the lower nitrogen rates which were closer to 5-6%. This may also correspond to the higher HSI values observed in those treatments receiving higher nitrogen applications for Cascade. For the Centennial hops, HSI did not appear to be impacted by nitrogen fertility treatments with all values falling with acceptable or good quality ranges and relatively consistent observed values for alpha acids (Table 27). Beta acids in the Centennials once again varied with the highest 100/150 lbs N ac-1 treatment showing lowest overall beta acid percentage and all other treatments having statistically similar values.

Table 26. Cascade fertility trial brew quality, Alburgh, VT, 2020.

Treatment Spring/Summer

Total applied N

Alpha acids

Beta acids

HSI

lbs N ac-1

lbs N ac-1

%

%

 

100

100

6.13

2.14

ab†

0.212

b

100/50

150

5.91

2.24

ab

0.276

ab

50/100

150

5.02

2.32

ab

0.378

ab

100/100

200

3.59

2.27

ab

0.639

a

50/150

200

3.85

2.46

a

0.524

ab

100/150

250

4.00

1.87

b

0.432

ab

LSD (0.10) ‡

 

NS ¥

0.489

 

0.385

 

Variety Mean

 

4.75

2.22

 

0.410

 

†Within a column treatments marked with the same letter were statistically similar (p=0.10). Top performers are in bold.

‡LSD –Least significant difference at p=0.10.

¥NS –No significant difference between treatments.

 

Table 27. Centennial fertility trial brew quality, Alburgh, VT, 2020.

Treatment Spring/Summer

Total applied N

Alpha acids

Beta acids

HSI

lbs N ac-1

lbs N ac-1

%

%

 

100

100

7.70

3.77

ab†

0.233

100/50

150

7.88

3.53

ab

0.235

50/100

150

7.28

3.87

a

0.311

100/100

200

6.94

3.41

ab

0.230

50/150

200

7.04

3.79

ab

0.319

100/150

250

7.30

3.32

b

0.251

LSD (0.10) ‡

 

NS ¥

0.50

 

NS

Variety Mean

 

7.36

3.62

 

0.263

†Within a column treatments marked with the same letter were statistically similar (p=0.10). Top performers are in bold.

‡LSD –Least significant difference at p=0.10.

¥NS –No significant difference between treatments.

Research conclusions:

GERMPLASM

Eleven landrace hops were collected from NY, MA, and VT over the project period. Unique characteristics from these germplasm varieties could provide unique branding opportunities for growers or brewers. As the project continues to develop, we hope to obtain additional wild hop samples from across the Northeast to build a database of genetically distinct cultivars of our wild hop species (Humulus lupulus var. lupulus and Humulus lupulus var. lupuloides). Yield data and other metrics need to be further evaluated as over multiple years to see if these lines can produce adequate yields. Wild hop varieties could provide new and distinct flavor profiles through variable acid and oil profile combinations for use by brewers. With the aim to build this database, new varieties could become available to regional hop producers that are more suitably adapted to our growing region through greater resistance to downy mildew and other prevalent and damaging pests and diseases. Furthermore, this could offer the potential to open up regionally adapted breeding experiments, which could allow us to select hop traits that would be beneficial for our growing region. Ideally, this would lead to improvements in the quality and consistency of hops for our growers and brewers in our ever-expanding craft brewing industry in Vermont and the rest of the Northeast.

You can find our annual germplasm reports (PDFs) with pictures uploaded here.

CROWNING

While increased pressure from downy mildew in this region gives us more to gain by crowning to remove overwintering downy mildew, our much shorter growing season makes the timing of this practice tricky. If we crown too late, we risk leaving too short a window for plants to reach the top of the trellis by late June. Our research from the past seasons indicates that there are benefits to crowning and that it is important to implement this practice as early as possible in the spring. Crowning can help to remove overwintering inoculum and to aid in warming the crown for plant growth. Early crowning helped to improve yields, whereas late crowning or uncovering appeared to have negative or marginal impact on our hops. We also experienced increased yields on flamed treatments this year perhaps helping to not only reduce potential overwintering inoculum but also potential bull shoots which would have produced fewer cones and reduced yields. This trial has also confirmed the risk of crowning too late: crowning seems to be helping to manage downy mildew pressure, but crowning after shoot emergence clearly reduced yield by shortening the growing window.

You can find our annual crowning reports (PDFs) with pictures uploaded here.

HARVEST TIMING

From the first year of the study, we noticed a general increase in the total analyzed oils from the early harvest period to the late harvest period for most varieties. Resin concentrations showed a bit more variation across varieties and harvest periods. In many cases, delaying harvest could lead to an increase in oil and resin levels contributing to increase aromatics in hop cones, whereas other varieties suggest that we may benefit from an earlier harvest period to similarly maximize oils and resins.

You can find our annual harvest timing reports (PDFs) with pictures uploaded here.

BENEFICIAL EXCLUSION STUDY

Hop production in the Northeast continues to rebound; many farmers are looking for additional information and clarity on how pests can impact their crop production. While we do not currently have an understanding on how beneficial insects can impact our pest populations, we hope to be able to quantify their impact through continued monitoring. Through our first year study, there were some distinct differences between our open and closed treatments, especially in a no-spray environment. Especially in environments with decreased insecticide applications we noticed smaller pest populations after one week of exposure versus those closed off from the environment. Conversely, conventional practices more often showed no effect in insect populations between treatments. In a more diverse low-spray environment, there is the potential to see more of an impact from predation of natural enemies.

See the 2017 Beneficial Exclusion Final Report (PDF) for more information

NITROGEN FERTILITY TRIAL

As mentioned earlier, Cascade hops within this trial appeared to be impacted greatly by poor growth when compared to the Centennial hops. This may be a result of systemic downy mildew problems or perhaps some viral infection. After normal side arm initiation and burr formation of the hops, plants seemed to develop little to no side-arm growth with much smaller clusters of hops developing directly from the main bines. As the season progressed it was also apparent that the cones from the Cascade hops did not fully develop a strig and cones were noticeably stunted. This in conjunction with lack of side arm development also made them much more difficult to harvest with a greater amount of leaf material pulled in the harvester. At the moment, it is unclear the main cause of poor growth for the Cascade hops in the trial, but plant tissues will be sent for analysis in the 2021 season for evaluation. In addition to noticeably poor cone development and growth, nutrient uptake may have been impacted by these problems in the Cascade hops. Throughout the trial, there were generally very few noticeable treatment effects for the Cascade hops this year, even when looking at total plant nitrogen from tissue analysis. As seen in the Centennial hops, there was a clear increase in total plant nitrogen with increases to nitrogen application rates whereas no effects were observed in the Cascade hops.

There were some slight similarities between 2019 and 2020 when looking at hop brewing quality. 2019 treatments appeared to illicit a more pronounced, negative response to increased nitrogen applications as both alpha acids and beta acids appeared to decrease when looking primarily at nitrogen treatments.  Some similarities were observed in the 2020 Cascade hops as well as beta acids overall, suggesting that excessive nitrogen rates may negatively impact levels of hop resins. Throughout both years, it is also apparent that nitrogen applications in this form have the potential to impact the uptake and availability of other nutrients in the plants. A wide array of factors can impact nutrient availability ranging from weather conditions to changes in soil pH, and it is known that nitrogen management within soil is closely linked to the uptake of a number of other nutrients. Other similarities were observed across years with highest hop aphid populations present in those plants receiving 200 lb N ac-1 of total nitrogen. Otherwise, most observed pest populations did not appear to be impacted by nitrogen treatments in either year, yet composition did differ from year to year with higher aphid populations present in 2019 and higher two-spotted spider mite populations present in 2020.

The use of an in-field nitrate meter could have the potential to become a useful tool with quick results. This would require some additional work to determine nitrogen fertility requirements corresponding to petiole nitrate readings for this crop. Based on some of the preliminary data collected in 2019, it appeared that the tested nitrogen rates provided adequate nitrogen fertility leading into the last week of vegetative growth. Lower applications of nitrogen may illicit a great response and deficiency in plants. Once again, dry conditions in summer months in addition to limited well capacity appeared to limit hop growth during vegetative production. May and June were particularly dry receiving nearly 3 inches less precipitation than the 30 year average. Greater precipitation and increased ability to irrigate may improve hop yields in conjunction with proper fertility. Given these growing conditions and evaluated treatments over the two years of study, it appeared as if differences in spring applications had little impact on plant growth on these soils and any differences were largely observed across the total nitrogen applications amount. Soils that are highly prone to leaching could also lead to greater nutrient loss, which may influence application rates and timing. In this case larger, single applications may want to be avoided in favor of split applications throughout the critical growth periods of vegetative production.

You can find our annual fertility reports (PDFs) with pictures uploaded here.

Participation Summary
4 Farmers participating in research

Education

Educational approach:

Field Days & Conferences

2/25/17 – 8th Annual UVM Hop Conference held in Burlington, VT had 165 attendees and 28 online participants. There were a variety of presenters both farmers, brewers, and researchers. Lily Calderwood, Heather Darby, and Scott Lewins presented on beneficial insects and IPM practices. Presentations highlighted fertility management and pest management especially in the afternoon beginner sessions. The project goals and performance target were introduced to the attendees. Attendees were given the opportunity to sign-up for the goScout program. There were 60 participants that signed up for the program. Conference proceedings can be found at http://www.uvm.edu/extension/cropsoil/hops.

7/27/17 UVM Crop and Soil Field Day held in Alburgh, VT had 325 attendees including farmers and stakeholders. The hop germplasm project was highlighted and a hop historian talked about historical hop production in VT. Farmers were also trained on pest scouting and how pest to identify beneficial insects in the hopyard. Crowing of hops was highlighted as well including preliminary research from the trial. Farmers were able to see crowning equipment in operation.

2/16/18 – 9th Annual UVM Hop Conference held in Burlington, VT had 126 attendees and 14 online participants. There were a variety of presenters both farmers, brewers, and researchers. Presentations highlighted fertility management and pest management especially in the afternoon beginner sessions. Conference proceedings can be found at http://www.uvm.edu/extension/cropsoil/hops. The goScout program and results from previous year were highlighted. Attendees were given the opportunity to sign up for goScout.

7/26/18 UVM Crop and Soil Field Day held in Alburgh, VT had 278 attendees including farmers and stakeholders. The hop germplasm and crowing projects were highlighted and preliminary data was shared with the audience. The hop fertility trial was toured and information on soil testing and analysis were provided to the attendees.

9/28/18 - Hop field day at Champlain Valley Hops held in Starksboro, VT had 40 attendees. The field day allowed growers to learn about scaling up hop production, variety and plant material selection, pest management, and weed management.  Field day on hop yard establishment for aspiring and current growers. Owner Peter Briggs and manager Julian Post hosted the event and provided information on the challenges of site selection, trellising, and planting a 22 acre yard to become the largest hop yard in Vermont.

2/21/19- 10th Annual UVM Hop Conference held in Burlington, VT had 89 attendees. The speakers included farmers from England and Oregon and researchers and brewers from Vermont. Day long event included release and training on new Virtual Reality Hop Scouting Tool developed by UVM. Also included research results reports on hop harvest timing, germplasm study, and crowning study results.

7/25/19 - Annual Northwest Crops and Soils Field Day  held in Alburgh, VT had 286 attendees. The theme ‘Twelve Years of Research – But Wait, There’s More’, tour included research trials on hops as well as other crops trials. Research tours of hops included information on scouting, pest identification, harvest timing, pest management, and germplasm study results.

2/28/20- 11th Annual HopsConferenceFlyer 2020 held in Burlington, VT had 71 attendees. The speakers included farmers from New York and researchers and brewers from Oregon, Michigan and Vermont. Day long event included research results reports on hop harvest timing, germplasm study, and crowning study results.

Due to the pandemic our team held a series of Virtual Field Day Fridays 2020 We did the Hop Harvest Timing video, which can be found here - https://www.youtube.com/watch?v=_XVfZ-tBFAc&feature=youtu.be. It was recorded 8/17/20 and currently has 102 views. Our YouTube site is http://www.youtube.com/users/cropsoilsvteams.

In late summer, a couple of small in-person events were held to further the network building between Brewer and Growers in New England. The attendance was capped at 25 people. The flyers include: Brewer and Grower Events 2020 and Brewers at CV Hops Event 2020.

In 2020, we had 3 blogs posted to What’s Hoppening. Topics listed below.

The What’s Hoppening blogs can be found at http://blog.uvm.edu/hoppenin

7/2/20, Japanese Beetles in Hops in the Northeast

6/24/20, Potato Leafthoppers have Arrived!

4/20/20 Early Season Management

 

Hop Power Hours- From 2017-2018 monthly, hour long webinars were held at the noon hour to help inform growers on seasonal specific topics taking place within the hop yard. Growers were encouraged to attend these “Hop Power Hours” with the intent to improve networking amongst growers and serve as teaching tools to assist farmers with on-farm practices and pest identification. A quick poll through the webinar platform allowed us to gauge learning outcomes and intent to change or implement new practices. The Hop Power Hours are than archived and posted on our website (www.uvm.edu/extension/cropsoil/hops) to allow for future viewing. As of January 7, 2018 the archived Hop Power Hours have had a total of 1992 views.

2017 Hop Power Hours

4/24/17 - David Gent: Downy mildew management in the spring had 24 Participants

Based on what you learned today, will you start/change a pest management practice? (Yes 13/24) (No response/require more information 11/24)

Did you learn anything new today? (Yes 22/24) (No response 2/24)

5/22/17 - Heather Darby: Soil fertility management in the Northeast hopyard had 22 Participants.

Based on what you learned today, will you start/change a nutrient management practice? (Yes 11/22) (No response/require more information 11/22)

Did you learn anything new today? (Yes 14/22) (No response 6/24) (Did not learn anything new 2/22)

6/26/17 - Lily Calderwood: Potato leafhopper management in hops had 13 Participants.

Based on what you learned today, will you start/change a pest management practice? (Yes 8/13) (No response/require more information 5/13)

Did you learn anything new today? (Yes 12/13) (No response 1/13)

7/31/17 - Andrew Landers: Pesticide application tools and technology had 15 Participants.

8/28/17 - Chris Callahan: Postharvest handling of hops had 18 Participants.

9/25/17 - Erica Cummings, Heather Darby: Hop quality, end of season observations had 13 Participants.

 

2018 Hop Power Hours

4/23/18 – Julien Venne: Mastering Spring activities in the hop yard had 27 participants.

As a result of what you learned, will you make a change on your farm or how you advise farmers? 89% (16/18)

As a result of the webinar, do you now have a better understanding of spring activities in the hop yard? 100% (Yes 18/18)

5/21/18 – Erin Lizotte: Powdery mildew in the hop yard had 18 participants.

As a result of what you learned, will you make a change on your farm on scouting for and treating powdery mildew? 100% (Yes 9/9)

As a result of the webinar, do you now have a better understanding of and ability to identify powdery mildew? 100% (Yes 9/9)

6/25/18 – Gene L’Etoile: One decade of growing hops: a farmer shares his experiences had 18 participants.

Will you implement a new practice or strategy from the information gained from the webinar? 100% (Yes 6/6)

Will the information gained from this webinar help you better manage fertility in your hopyard? 67% (Yes 4/60

7/23/18 – Trevor Hardy: Information on irrigation systems for hop production  had 19 participants.

As a result of the webinar, do you now have a better understanding on irrigation systems for hop production? 100% (Yes 11/11)

As a result of what you learned, will you make a change in your current hop yard? 82% (Yes 9/11)

8/27/18 – Lily Calderwood: Harvest timing and the effect on quality of hops had 21 participants.

As a result of the webinar, do you feel better prepared to harvest your hops on time? 100% (13/13)

As a result of what you learned, will you make a change in your current hop yard?    69%  (9/13)

10/1/18 – Melanie Lewis Ivey: Information on hop viruses and viroids had 16 participants.

As a result of the webinar, do you now have a better understanding of and ability to identify viruses on hops? 100% (Yes 8/8)

As a result of what you learned, will you make a change on your farm on scouting for and treating viruses? 100% (Yes 8/8)

2017, 2018, 2019 Hop Blogs

During the 2017 and 2018, there were 25 blog posts developed and posted to the UVM What's Hoppening Blog. The blog has 273 followers from the region and Canada. The blog posts highlighted field days, conferences, the Hop Power Hour, and goScout. In addition, timely field topics were written about to help farmers make management decisions during the growing season. There were 8 blog posts focused on disease and insect pest scouting and management. Additional blog posts were focused on irrigation, harvest timing, soil management, and general hop production techniques. The What's Hoppening Blog can be found at http://blog.uvm.edu/hoppenin/.

2017 and 2018 Hop goScout Program

From 2017-2018 Monthly surveys were sent out to growers as a means of gauging interest in topics, encourage timely field operations, and prompt growers to scout their hop yards for pests, diseases, and fertility issues. There were 60 farmers that signed up for the goScout program in spring of 2017 but throughout the season approximately 25 to 30 farmers answered the survey each month.

April 2017 - Introductory Survey, topic interest with 60 participants responding to the goScout Survey.

As a result of this goScout:

33% of growers had an interest in learning more about pest identification and management.

20% of growers had an interest in learning more about proper fertilization practices.

5% of growers had an interest in learning more about timing of field operations including harvest timing.

20% of growers had an interest in learning more about each of the above categories.

6% of growers had an interest in learning more about marketing, biodynamics, terroir, or processing.

May 2017 - Scouting, downy mildew management, fertilizing with 30 participants responding to the goScout survey. 

As a result of this goScout:

16% of growers planned to take no additional actions.

47% planned on implementing crowning/pruning practices to reduce downy mildew inoculum.

23% planned on developing/implementing a regimented scouting schedule.

14% had no response

June 2017 - Scouting for early season hop pests with 23 participants answering the survey.

As a result of this goScout:

23% of growers planned to take no additional actions.

8% planned on pruning for aerial downy mildew spikes.

46% of growers planned to adjust their pesticide applications based on their scouting results.

23% of growers planned to continue scouting as part of their routine.

July 2017 - Scouting for mid-season hop pests and managing pesticide application with 30 participants answering the survey.

As a result of this goScout:

15% of growers planned to take no additional actions.

8% planned on adjusting their fertilizer applications based on soil tests and hop observations.

62% of growers planned to adjust their pesticide applications based on scouting results.

15% of growers had no response

*23 out of 40 total participants were new to goScout in 2018 and had not participated in any goScout survey in the past.

Reached out to 78 individuals, 40 initial responses.

April 2018 - Introductory Survey, topic interest with 40 participants answering the first survey.

*23 out of 40 total participants were new to goScout in 2018 and had not participated in any goScout survey in the past.

As a result of this goScout:

25% of growers had an interest in learning more about pest identification and management.

13% of growers had an interest in learning more about proper fertilization practices.

3% of growers had an interest in learning more about timing of field operations including harvest timing.

15% of growers had an interest in learning more about each of the above categories.

3% of growers had an interest in learning more about marketing or processing.

41% of growers proffered no response.

May 2018 - Training, crowning, downy mildew scouting with 37 farmers answering the survey.

As a result of this goScout:

18% of growers planned to take no additional actions.

5% planned on adjusting their early season fertilizer applications based on learned information.

18% planned on adjusting their training times based on learned information.

12% planned on implementing crowning/pruning practices to reduce downy mildew inoculum.

18% planned on developing/implementing a regimented scouting schedule.

June 2018 - Early season pest and disease scouting with 22 farmers answering the survey.

As a result of this goScout:

67% of growers planned to continue scouting as part of their routine.

33% of growers planned to adjust their pesticide applications.

July 2018- Mid season hop pest and disease scouting, and irrigation management with 32 farmers answering the survey.

As a result of this goScout:

60% of growers planned on adjusting their irrigation practices.

20% of growers planned on adjusting their pesticide applications.

20% of growers planned on making no change.

August 2018- Late season hop pest and disease scouting, and harvest timing with 27 farmers answering the survey.

As a result of this goScout:

29% of growers planned on adjusting their harvest timing.

29% of growers planned on adjusting their pesticide applications.

42% of growers planned on making no change.

 

Milestones

Milestone #1 (click to expand/collapse)
What beneficiaries do and learn:

300 farmers will learn about pest and nutrient management techniques at our 2016 workshops or our 2016 Annual Hop Conference. Project information including goals will be shared and 30 interested farmers will be provided with yield and pest recordkeeping ID cards.

Proposed number of farmer beneficiaries who will participate:
300
Proposed number of agriculture service provider beneficiaries who will participate:
5
Actual number of farmer beneficiaries who participated:
378
Actual number of agriculture service provider beneficiaries who participated:
102
Proposed Completion Date:
December 30, 2016
Status:
Completed
Date Completed:
February 28, 2017
Accomplishments:

The project performance target and project objectives were presented to attendees at the 2016 Annual New York Hop Conference held December 3, 2016 in Morrisville, NY. The conference had 285 attendees included farmers and stakeholders. The same information was presented at the UVM Annual Hops Conference held in Burlington on February 24, 2017. The conference had 193 attendees from around the region and Canada. Both conferences had presentations focused on pest and fertility management given by farmers and researchers.

At the hops conferences farmers were asked to sign-up if they were intersted in particiipated in the goScout program throughout the summer. 60 farmers signed-up to participate in yield and pest recordkeeping ID program.

Milestone #2 (click to expand/collapse)
What beneficiaries do and learn:

30 interested farmers will be provided with yield and pest recordkeeping ID cards. The 30 growers will monitor pests, learn identification of major pests, and implement at least one new pest management and one new nutrient management practice as identified through applied research by spring 2019.

Proposed number of farmer beneficiaries who will participate:
30
Proposed number of agriculture service provider beneficiaries who will participate:
5
Actual number of farmer beneficiaries who participated:
53
Proposed Completion Date:
June 3, 2019
Status:
Completed
Date Completed:
January 1, 2019
Accomplishments:

2017 and 2018 Hop goScout Program

From 2017-2018 Monthly surveys were sent out to growers as a means of gauging interest in topics, encourage timely field operations, and prompt growers to scout their hop yards for pests, diseases, and fertility issues. There were 60 farmers that signed up for the goScout program in spring of 2017 but throughout the season approximately 25 to 30 farmers answered the survey each month. In 2018 23 new growers signed up for goCrop. It is estimated that approximately 58 different growers participated in the Hop goScout Program throughout 2017 and/or 2018. Each week 22 to up to 40 farmers completed the goScout Program.

April 2017 - Introductory Survey, topic interest with 60 participants responding to the goScout Survey.

As a result of this goScout:

33% of growers had an interest in learning more about pest identification and management.

20% of growers had an interest in learning more about proper fertilization practices.

5% of growers had an interest in learning more about timing of field operations including harvest timing.

20% of growers had an interest in learning more about each of the above categories.

6% of growers had an interest in learning more about marketing, biodynamics, terroir, or processing.

May 2017 - Scouting, downy mildew management, fertilizing with 30 participants responding to the goScout survey. 

As a result of this goScout:

16% of growers planned to take no additional actions.

47% planned on implementing crowning/pruning practices to reduce downy mildew inoculum.

23% planned on developing/implementing a regimented scouting schedule.

14% had no response

June 2017 - Scouting for early season hop pests with 23 participants answering the survey.

As a result of this goScout:

23% of growers planned to take no additional actions.

8% planned on pruning for aerial downy mildew spikes.

46% of growers planned to adjust their pesticide applications based on their scouting results.

23% of growers planned to continue scouting as part of their routine.

July 2017 - Scouting for mid-season hop pests and managing pesticide application with 30 participants answering the survey.

As a result of this goScout:

15% of growers planned to take no additional actions.

8% planned on adjusting their fertilizer applications based on soil tests and hop observations.

62% of growers planned to adjust their pesticide applications based on scouting results.

15% of growers had no response

*23 out of 40 total participants were new to goScout in 2018 and had not participated in any goScout survey in the past.

Reached out to 78 individuals, 40 initial responses.

April 2018 - Introductory Survey, topic interest with 40 participants answering the first survey.

*23 out of 40 total participants were new to goScout in 2018 and had not participated in any goScout survey in the past.

As a result of this goScout:

25% of growers had an interest in learning more about pest identification and management.

13% of growers had an interest in learning more about proper fertilization practices.

3% of growers had an interest in learning more about timing of field operations including harvest timing.

15% of growers had an interest in learning more about each of the above categories.

3% of growers had an interest in learning more about marketing or processing.

41% of growers proffered no response.

May 2018 - Training, crowning, downy mildew scouting with 37 farmers answering the survey.

As a result of this goScout:

18% of growers planned to take no additional actions.

5% planned on adjusting their early season fertilizer applications based on learned information.

18% planned on adjusting their training times based on learned information.

12% planned on implementing crowning/pruning practices to reduce downy mildew inoculum.

18% planned on developing/implementing a regimented scouting schedule.

June 2018 - Early season pest and disease scouting with 22 farmers answering the survey.

As a result of this goScout:

67% of growers planned to continue scouting as part of their routine.

33% of growers planned to adjust their pesticide applications.

July 2018- Mid season hop pest and disease scouting, and irrigation management with 32 farmers answering the survey.

As a result of this goScout:

60% of growers planned on adjusting their irrigation practices.

20% of growers planned on adjusting their pesticide applications.

20% of growers planned on making no change.

August 2018- Late season hop pest and disease scouting, and harvest timing with 27 farmers answering the survey.

As a result of this goScout:

29% of growers planned on adjusting their harvest timing.

29% of growers planned on adjusting their pesticide applications.

42% of growers planned on making no change.

Milestone #3 (click to expand/collapse)
What beneficiaries do and learn:

4 farmer collaborators will assist with the development and implementation of research to identify best pest and nutrient management practices from August 2016 through July 2019.

Proposed number of farmer beneficiaries who will participate:
4
Actual number of farmer beneficiaries who participated:
4
Proposed Completion Date:
June 3, 2019
Status:
Completed
Date Completed:
February 1, 2019
Accomplishments:

On-farm research and farmer collaborators have been an important component of this project. In 2017, 3 farms participated in the Hop Beneficial Exclusion trial to evaluate the impact/benefit of having beneficial insects on hop farms. Farmers helped to collect data, communicate with researchers, and also presented at the hops conference. The hop harvest timing study had one on-farm collaborator in 2017 and 3 on-farm collaborators in 2018. Farmers assisted with hop cone collection at appropriate harvest times. They were responsible for hop cone collection, and shipment for aroma analysis. They presented the data at the 2019 conference and also work with brewers on a presentation.

Milestone #4 (click to expand/collapse)
What beneficiaries do and learn:

The 30 growers will learn how to take a soil sample, how to read the soil test results, and how to implement fertility changes based on the results by spring 2019.

Proposed number of farmer beneficiaries who will participate:
30
Proposed number of agriculture service provider beneficiaries who will participate:
5
Actual number of farmer beneficiaries who participated:
86
Actual number of agriculture service provider beneficiaries who participated:
19
Proposed Completion Date:
June 3, 2019
Status:
Completed
Date Completed:
November 1, 2018
Accomplishments:

Soil testing and fertility information was provided at 2 hands-on workshops and at 2 conferences. Specifically farmers learned the following items:

  1. How to take a soil test and get the sampled analyzed.
  2. How to read a soil test and make a recommendation.
  3. When to add fertility and how much to add to the hop plant depending on the age of the crop.
  4. How to apply fertilizer through the drip line or irrigation.
  5. Types of fertilizers.
Milestone #5 (click to expand/collapse)
What beneficiaries do and learn:

500 farmers will learn best pest and nutrient management practices through outreach
materials distributed through the web (webinar, video). They will also learn about the importance of soil sampling and learn how to take, read, and make amendment according to the results of their soil test. This is the final goal for the fertility aspect of this project for completion in spring 2019.

Proposed number of farmer beneficiaries who will participate:
500
Proposed number of agriculture service provider beneficiaries who will participate:
5
Actual number of farmer beneficiaries who participated:
2973
Actual number of agriculture service provider beneficiaries who participated:
254
Proposed Completion Date:
June 3, 2019
Status:
Completed
Date Completed:
July 25, 2019
Accomplishments:

Through this project a total of 3,227 stakeholders have learned about best pest and nutrient management practices through outreach materials distributed through the web (webinar, video, blogs, conference proceedings). They have also learned about the importance of soil sampling and learn how to take, read, and make amendment according to the results of their soil test.

A few examples of these materials include:

The Hop Harvest Timing video, which can be found here – https://www.youtube.com/watch?v=_XVfZ-tBFAc&feature=youtu.be. It was recorded 8/17/20 and currently has 102 views. Our YouTube site is http://www.youtube.com/users/cropsoilsvteams.

In 2020, we had 3 blogs posted to What’s Hoppening. Topics listed below.

The What’s Hoppening blogs can be found at http://blog.uvm.edu/hoppenin

7/2/20, Japanese Beetles in Hops in the Northeast

6/24/20, Potato Leafthoppers have Arrived!

4/20/20 Early Season Management

Milestone Activities and Participation Summary

Educational activities:

156 Consultations
24 Curricula, factsheets or educational tools
4 On-farm demonstrations
12 Online trainings
18 Webinars / talks / presentations
9 Workshop field days
9 Other educational activities: Other activity includes the goScout Program offered to farmers to help them learn how and when to scout for certain pests and beneficial insects.

Participation Summary:

891 Farmers
323 Number of agricultural educator or service providers reached through education and outreach activities

Learning Outcomes

225 Farmers reported changes in knowledge, attitudes, skills and/or awareness as a result of their participation
75 Agricultural service providers reported changes in knowledge, skills, and/or attitudes as a result of their participation
Key areas in which farmers reported changes in knowledge, attitude, skills and/or awareness:

Through the Hop Power Hour and the goScout Program farmers were provided information about pest scouting, monitoring, evaluation and identification. The pests that farmers were taught about included diseases (i.e. downy and powdery mildew) and insect pests (spider mites, aphids, Japanese beetles) as well as beneficial insects (mite destroyers, lady bugs).  In addition, farmers were provided information on soil testing, fertility amendments, soil test interpretation, and fertility management. Other areas where knowledge was provided included general hop management such as crowning, training, and irrigation. Harvest timing and quality monitoring were also topics offered to the stakeholders. Survey tools through quick polls following webinars and survey monkey were used to document knowledge and skills gained by farmers.

Through the hop conferences and field days farmers were provided information on pest scouting, monitoring, evaluation and identification. The pests that farmers were taught about included diseases (i.e. downy and powdery mildew) and insect pests (spider mites, aphids, Japanese beetles) as well as beneficial insects (mite destroyers, lady bugs).  In addition, farmers were provided information on soil testing, fertility amendments, soil test interpretation, and fertility management. Other areas where knowledge was provided included general hop management such as crowning, training, and irrigation. Harvest timing and quality monitoring were also topics offered to the stakeholders. Farmers gained valuable information on marketing and hop management through listening researchers and other experienced hop farmers. Post event surveys were administered through survey monkey.

Performance Target Outcomes

Target #1

Target: number of farmers:
40
Target: change/adoption:

Farmers will make a change to or adopt a new pest or fertility management practice.

Target: amount of production affected:

100 acres will be affected by the change or adoption of new pest or fertility management practices.

Target: quantified benefit(s):

Farmers will benefit by increasing yields by 400 lbs per acre and increasing revenue by $6,000.

Actual: number of farmers:
53
Actual: change/adoption:

Farmers reported a number of changes to pest or fertility management plans. 16 farmers adopted weed management practices. 17 farmers started crowning hops to control downy mildew. 3 implemented practices to enhance beneficial insects. 5 farmers began implementing a regular scouting regime. 12 farms adjusted fertility programs by either changing rates or timing of fertility applications.

Actual: amount of production affected:

There were a 142 acres affected by the pest and fertility management changes.

Actual: quantified benefit(s):

Farmers benefited by increasing yields between a reported 50 and 800 lbs per acre and increasing revenue between $650 and $10,400 per acre.

Target #2

Performance Target Outcome Narrative:

Forty farms in the Northeast will adopt at least one new pest and/or nutrient management practice on a total of 100 acres and as a result their average hop yield increases by 400 lbs per acre resulting in a increased gross revenue of $6,000 per acre.

The project team worked closely with over 120 producers throughout the duration of the project. Direct involvement with producers helped to track and monitor progress in learning, trying new practices, practice adoption, and the impact the new practices had on the farm yield and quality. To verify the performance target hop farmers that participated in 56 goScout, 3 on-farm research, and 26 farm advisors were surveyed at various points along the project timeline. Initially farmers were provided a pre program survey to understand level of knowledge in the broad area of pest and fertility management. The initial survey went out to 85 farmer stakeholders. Baseline survey results indicated that only 32% of farmers were confident with their pest management plan and 40% with their soil fertility management. A final survey was distributed to the same group in February of 2020. At this time the results indicated that 66% of the farmer felt confident with their pest management plan and 78% felt confident with their fertility management program. Overall, 57% of the farms reported that pest pressure had been reduced significantly and 35% were able to reduce pesticide usage and/or adopt a lower impact pesticide.  

Of the 85 farms surveyed, 53 farms graciously provided information on specific practices adopted/modified and relationship to yield and quality. These farms represented 142 acres with the majority of the farms have 2 to 5 acres of hops in production. 25 of the farmers reported that they were able to improve hop quality and also as a result be able to increase markets. Farmers reported that they had made a number of changes to pest or fertility management programs. 16 farmers adopted new weed management practices. 17 farmers started crowning hops to control downy mildew. 3 implemented practices to enhance beneficial insects. 5 farmers began implementing a regular scouting regime. 12 farms adjusted fertility programs by either changing rates or timing of fertility applications. These 53 farms reported varying impacts on yield, with some farmers documenting an increase in hop yield of 50 lbs per acre and others up to 800 lbs per acre. The farmers reported that the average price paid for hops was $13 per dried pound. Hence the impact per acre ranged from $650 to $10,400 depending on the farm.  

53 Farmers changed or adopted a practice

Additional Project Outcomes

2 Grants applied for that built upon this project
1 Grant received that built upon this project
$33,591.00 Dollar amount of grant received that built upon this project
5 New working collaborations
Success stories:

As a result of our ongoing studies and events, we have had established a focal point for germplasm collection and cultivated an interest in developing hops as a renewed and improving crop in the Northeast. In addition to the 10 original farmers to supply wild hop samples, we have had an additional 3 farmers who have offered and will supply new wild hop varieties for the study. Furthermore a farmer in Northeast Vermont, who provided 2 wild hop varieties, is looking to apply for farmer grants to develop his own hopyard and brewery in conjunction with his existing agritourism business. As a result of existing research, he hopes to 1.) further explore spacing, trellising, and location selection to optimize plant growth and decrease disease pressure 2.)  cultivate his wild on-farm variety for hop production and use in the new brewery and 3.) begin crossing native, wild males with existing hop varieties to cross in west coast flavors.

The farmer continued in his enthusiasm for his project and inspiration and noted, “I’m confident in the local market for hops.  This could open up a plethora of doors for farmers and brewers to make some hyperlocal beer in a state where craft beer is synonymous with maple syrup.” Vermont is well known for maple syrup and craft beer industries and further research proves to not only provide information but inspiration to our farmers. 

One farmer collaborating in this project was having a difficult disease issue that he had not been able to identify. The disease had become so prevalent he was not able to salvage any yield from 2 of his varieties. Through this project, he enrolled in the weekly scouting program and ID Hours. This led to a visit from our team, collection of diseased hop cones, and finally correct identification of the disease. Although the disease had never been identified in our region, we worked with plant pathologists from WA and OR to figure out the casual agent.  From that point we were able to put together a disease management plan to help reduce the pressure. 

Another farmer was able to reduce spray applications because they participated in the weekly scouting program and ID hours. This particular farmer was spraying on a regular schedule and not paying much attention to the level of pest pressure prior to spraying. Through this program the farmer started scouting weekly and making spray decisions based on pest pressure and weather conditions. In the final year of the project, the farmer noted reducing spraying times by an average of 30% each year (with some years being over 50% reduction). In the final year the reduction led to 5 less sprays of fungicide. Each fungicide spray costs $30 per acre so this is a cost saving of $150 an acre over the season. Obviously less pesticide spray also has significant environmental benefits.

Assessment of Project Approach and Areas of Further Study:

The educational methods deployed as part of this project were very successful and led to rapid changes in farm integrated "pest management programs (IPM). Farmers were provided with initial training on pest identification and scouting techniques during the winter conference. Farmers signed up to receive weekly surveys that helped them scout for pests that would likely be an issue during that time of the season. The survey included photos of pests, scouting instructions, and a recording function. Once they completed their survey, they received results and some management options. Farmers also joined in on the ID Hour webinar to further help with management. This combination of education and support services helped farmers adopt changes and increase pest management on their hop farms. 

The research conducted during the project period created many new questions that should be explored to further. To start new diseases were identified as part of the project. The diseases were primarily found on the cones and many of the diseases were not considered of economical significance in other hop growing regions. Hence work needs to be conducted to better understand these cone diseases in the northeast. First a farm level survey should be conducted to determine the extent and types of cone diseases plaguing northeastern hopyards. Second lifecycle of the disease should be understood to help to determine proper management options. Lastly, control and management options should be tested. 

The beneficial insect research clearly showed that possible management of beneficial insects can help reduce pest pressure. How pests were managed on each type of farm really impacted the ability of beneficial insects to colonize and build appropriate populations to control pests. Further research needs to be conducted to determine farm management practices that minimize impact on the beneficial population while still being able to maintain high yields and quality. 

Development of adequate nitrogen recommendations for our region requires a longer term study with more mature hop plants. Unfortunately, our hop nitrogen rate study was limited by the fact that we had young hop plants that require smaller quantities of nitrogen compared to more mature plants. Hence the data from this project provided important information on fertilizing new stands of hops. Future research should focus on fertility trials in mature hops.

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Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.