Final report for FW20-358
Project Information
Irrigated systems in Lake County are used for grazing or hay production, as primary agricultural products of the county are beef cattle and hay (USDA Census of Agriculture, 2017). Irrigated systems provide regular water supply for growing livestock forages on the deeper soils in the county. Over time, soil nutrients have been depleted and perennial forage species have declined in quantity and quality. The common mode of operation is to till up the existing pasture and establish a new one. However, this is a cost expensive strategy with no realized profit until the second year.
Our project site is on old pasture system, dominated by Kentucky Bluegrass (Poa Pratensis) which has formed a thatch layer and has a physiological dormancy in mid summer; so, irrigation is ineffective at producing feed for half of the growing season. As irrigation cost is high, other strategies for increasing pasture productivity need to be employed.
We will divide the pasture blocks (replicates) and interseed improved pasture species (Treatment 1) or a mix of cover crops (Treatment 2) . One subplot will not be overdrilled as the control (Treatment 3). Prior to planting, the site will be grazed to provide light and effective irrigation for germinating seedlings. Following establishment of the overseeded plants, pasture will be grazed in late summer. We will collect data on seasonal pasture biomass yields, forage nutritional quality, grazing days, soil quality, and cost of production. We will share our trial results with farm field days, a peer reviewed fact sheet, and presentations with agricultural groups including youth.
Our objectives are all attainable with our team approach, equipment on hand, and timeline we propose
| Objective | Measurement Method | Accountability | Time Line |
|
Extension of grazing days |
Cow numbers will be tracked using PastureMap software |
John will monitor cattle numbers |
May 2020 - September 2021 |
|
Increase soil health on pasture |
Soil quality tests pre grazing and planting (May 2020); soil quality tests post planting, and post grazing (September 2020); soil quality tests - May 2021 and May 2022 |
Fara and farm assistant will core soil samples |
May 2020 - September 2020 May 2021, may 2022. Project was modified with end date of 09/01/2021 due to the need for interseeding twice in 2020. This alteration to our original plan was beneficial for our results but required us to end the project earlier by a year. This modification was approved by western SARE |
|
Increase pasture biomass and productivity |
Exclosure cages per treatment area will be clipped during active growing periods and compared with control exclosure which will also be clipped |
Serkan will provide exclosure cages and John will place in field with farm assistant and Fara's guidance. Graduate student and Fara will clip caged areas. Serkan will process samples to determine DM production and nutritive value |
Starting from July 2020, during active growing seasons. |
|
Determine if no till interseeding in existing pasture is effective long term |
Interseeded areas will be marked with a GPS and revisited in May 2021 pre cattle entry to determine perennial plant viability as well as carryover from annual plant |
Fara will GPS the interseeded areas |
June 2020 and May 2021 |
Cooperators
- (Researcher)
- (Educator and Researcher)
- - Producer
Research
Plot design: Our project will be implemented on a 22 acre pivot irrigated field in Lake County Oregon which is comprised of a single soil type: (Drews Loam 73 B 0-5% slope; Ecological Site: Loamy 14-18 PZ). In mid-May 2020, the pasture will be grazed at a high stocking density to remove the growing vegetation in preparation for interseeding. During the first week of June 2020, a no till drill (Great Plains TM) with a 10 foot planting width will be rented from Lake County Soil and Water District. This will be used to interseed the pasture in three blocks (replicates) of approximately 7.3 acres each with either a diverse mix of pasture or a mix of annual cover crops (Table 1). Planting will occur in randomized plots within each block with the following mixes that are identified in Table 1. Control will be three buffers in each block 100 feet wide that will be left unseeded. Plant species have been chosen for their soil health benefits (USDA, 2012) as well as grazing potential. Nine exclosure cages (a total of 27 cages) will be placed in each pasture treatment.
Table 1. Treatment planting mixes and seeding rate with plant-soil targeted objective (2020)
| Treatment | Planting Mix | Seeding rate (lbs) Pure Live Seed | Targeted Objective | Plant Life Cycle |
|
TRT1 Diverse Pasture Mix |
Orchard Grass Tall Fescue Alfalfa Sainfoin Birdsfoot Trefoil Plantain Chicory Spotted Medic Balansa clover |
4 15 5 30 4 4 2 4 3 |
Soil health increase through nitrogen fixation, positive mycorrhizal fungi association Higher grazing quality |
Perennial and potential self -regenerating annuals |
|
TRT2 Annual Cover Crop |
Brassica (Pasja turnip) Radish (Bio till radish) Forage oat Sudan grass
|
3 2 15 45
|
Soil health increase through thatch penetration, erosion reduction, increase in soil organic matter, and the capture, recycle, and redistributing of nutrients in the soil profile Higher grazing quantity and quality |
Annual |
| CONTROL | No interseeding on 100 foot wide strips |
Planting protocol: All seeds will be planted based on PLS (pure live seed) rates to the appropriate depth. Legumes will be inoculated with the species specific inoculum. Fertilizer will be applied at moderate levels based on soil test results to help newly germinating pastures.
Soil Health Measurements: Soil nutrient profile will be measured both pre and post grazing within three days of entry and exit, in fall 2020. Additionally, soil will be sampled in May 2021 and May 2022 pre grazing entry to determine possible extended soil benefits.
Soil samples will be cored randomly in triplicates per block treatment, and the samples will be composited and submitted per block for each treatment including control. Soil samples will be taken at a depth of 6 - 12 inches and analyzed for pH, organic matter, bulk density, nitrates, phosphorus, potassium, sodium, magnesium, calcium, sulfur, manganese, iron, copper, and zinc.
Forage Quantity and Quality Measurements:
Dry matter production (lb/acre) and herbage growth rates (lb/acre/d) will be measured during active growth in spring, summer, and autumn. Herbage growth will be measured from a rectangular quadrat, harvested using electric hand clippers to a stubble height of approximately 2 inch. After collecting the forage cuts, the plots will all be mowed to the same height approximately 2 inch using a rotary mower. All herbage from the quadrate cuts will be oven dried at 140 F for 48 hours. Forage cuts will be sub-sampled for sorting into botanical fractions (sown forage, weed, dead material) before drying. Herbage growth rates will be calculated at each harvest by dividing total DM production by the number of elapsed days since the previous harvest. As animal unit months (AUMs) are measured by dry matter weight of forage, AUMs will be assigned to each forage variety, extrapolated to a per acre basis. Sub-samples of the mixtures will be also subjected to wet chemistry forage quality analyses which will include crude protein, acid detergent fiber, neutral detergent fiber, lignin, and nitrates. Nutritive values of the forage samples will be determined in both years (establishment year and the following year).
Total Grazing Days on Pasture
Grazing days will be monitored through Pasture Map software. Cow size will be determined and converted to AUM equivalent. Pairs will be allocated both in mid May and later in late July. Pasture and animal health will be monitored visually throughout that time period. Summer grazing will terminate when forage has been grazed to a height of 4 inches overall.
Measurement of Project Success
The project will be successful if our objective of increasing grazing days and soil biodiversity are met. Benchmark measurements of soil health will serve as a foundation for comparing our consecutive measurements through time (2.5 years). In addition, grazing days are expected to increase for the first year with both our mixes (annual and perennial), and beyond with our perennial diverse mix establishing over time. Costs of production should not outweigh net profits. These will be measured for the duration of 2.5 years.
Plots were seeded accordingly in mid-May 2020 but due to seed failure and existing perennial competition, re-seeding occurred in early July 2020. The latter seeding was successful and provided greater forage quality in the fall of 2020 as represented in the table below. This increase in forage quality allowed for 92 cow/calf pairs to be grazed , beginning on September 23, 2020 for one week. Timing of seeding was a critical lesson learned. Due to the need for interseeding twice in 2020 and the additional costs incurred with the double interseeding effort, the project had to end at an earlier date, late summer 2021. However, the information on timing of interseeding was a valuable lesson learned, and in our opinion was worth the dual interseeding effort. The novel forage species that were planted in mid July 2020 (the second interseeding) were initially expected to increase forage quality and soil health in 2021, however historic drought rendered this objective impossible for 2021. A narrative after Table 3 explains the drought impact in greater detail.
Table 2. Plant dry matter biomass by treatment after second interseeding, 2020
|
Sep 16. 2020 |
Control
|
Forb mix
|
Cover crop mix |
Legume mix |
Birdsfoot trefoil **
|
SEM |
P value |
|
Forage production, lbs/acre DM* |
1,322 |
1,055 |
917 |
1,080 |
2,230 |
421 |
0.17 |
|
Legume, % |
0b |
15a |
1b |
10a |
40 |
1.7 |
0.01 |
|
Acid Detergent Fiber, % |
26.5 |
23.7 |
24.4 |
25.3 |
21.3 |
0.79 |
0.14 |
|
Neutral Detergent Fiber, % |
52.4 |
48.5 |
50.7 |
50.0 |
35.0 |
1.01 |
0.12 |
|
Ether Extract, % |
2.6 |
2.7 |
2.6 |
2.6 |
2.5 |
0.19 |
0.99 |
|
Crude Protein, % |
9.4c |
12.7a |
10.6b |
11.3b |
21.1 |
0.30 |
0.01 |
Results are significantly different from each other within row if lower case letters following numbers are different
* DM = dry matter
**birdsfoot trefoil results were from three year prior plantings in this project field and were included to show potential for long term viability of trefoil as an interseeded forage
In 2021, a historic drought rendered irrigation impossible for our normally pivot irrigated field. The result of no water and extremely dry conditions (see attached National Oceanic and Atmospheric drought map). Our project field dried up and interseeded forages from last year were not present (see attached picture). Amazingly, the birdsfoot trefoil from 2017 was still present and while growth was short, it was alive and functioning (see attached picture)
This overall project resulted in highly useful information for the producer, the agricultural community of Lake County, and University faculty and Extension focusing on forages. As a result of this project, we were able to determine appropriate timing of planting interseeded forages with a focus on warm season legumes for increased grazing and soil health. These interseeded forages were replanted in 2020 in July, following a failed May planting. We realized competition from existing cool season grasses was too detrimental to our early season planting, but our modified mid summer planting produced noticeably successful results. We were able to determine that berseem clover, red clover, chicory, plantain, and white clover succesfully established the first year with our second timed planting. Prior interseeded birdsfoot trefoil from 2017 in the same field had not only established but was thriving. Birdsfoot trefoil was a component of this project's seeding efforts, and our results from 2017 are a good model for potential of this forage species' contribution for enhanced grazing opportunities and soil renovation objectives.
This project has successfully provided the foundation for future research efforts through interseeding perennial grass pastures in eastern Oregon. This effort will continue with this producer as well as five other producers in the newly funded western SARE Professional + Producer grant OW21-365 titled "Overseeding novel forages in Oregon as a model for enhancing perennial grass pastures in the Pacific Northwest"
Dry Project Field, 2021
Soil tests were conducted in 2020 pre graze and pre plant in May and revealed high variability for nitrate and phosphorus within the field. In 2021, soil tests were conducted again in May, but the field was not irrigated due to extreme drought and lack of available irrigation water. Sampled soil samples in 2021 reveal extremely low nitrate levels, most likely due to desert like conditions and no irrigation. Phosphorus in 2021 showed high variability with one of the treatment samples at a noticeably higher level. The reasons for this are unclear. The samples from 2020 and 2021 are unfortunately cannot be truly comparable due to a different collection method in 2021. Each treatment was cored once for soil, and four replicates were composited for a single sample. Soil samples in 2021 were composited within treatments, with only one cored sample per replicate due to the extreme hardpack of the soil from drought.
Table 3. Soil properties: pH, nitrates, and phosphorus per treatment in pre grazed and pre planted field (May 2020), followed by resampling in May 2021
| Treatment 1 | Treatment 2 | Treatment 3 | Control | ||
| pH | 2020 Avg. (SD) | 7.08 (0.64) | 6.93 (0.50) | 6.65 (0.06) | 6.60 (0.16) |
| 2021 composite | 6.80 | 7.00 | 6.80 | 7.00 | |
| NO3 ppm | 2020 Avg. (SD) | 16.60 (7.42) | 13.00 (7.70) | 11.50 (7.05) | 7.75 (2.06) |
| 2021 composite | 3.00 | 3.00 | 3.00 | 2.00 | |
|
P ppm |
2020 Avg. (SD) | 13.00 (2.99) | 12.50 (2.65) | 12.25 (2.06) | 11.00 (1.41) |
| 2021 composite | 25.00 | 12.00 | 68.00 | 20.00 |
NO3 = nitrate, P = phosphorus, SD = standard deviation
In 2021, the level of soil sampling in the prior year was not possible due to historic drought and dry pastures. Sampling was extremely difficult at the level of intensity as 2020. Therefore, a composite soil sample was taken by treatment with one soil sample per replicate. Standard deviation was not possible with this method. Therefore, results were reported as composite only
Research Outcomes
Education and Outreach
Participation Summary:
This same article above appeared in the Bend Bulletin
Cover Crops council - Dec.17th presentation FINAL
Link for virtual webinar: https://www.youtube.com/watch?v=t3HYpZ6U-IA&feature=youtu.be
Field Days: Two field days will be held at the project site (Shine Brothers Ranches). Both will be in the fall after grazing terminates. Presenters will include John Shine, Serkan Ates, and Fara Brummer at the first field day and an invited speaker at the second field day.
Year 1: A tour of the project site will occur with follow up discussion on cover crops and application to grazing and soil health. A panel discussion will allow the project team to document interest in cover crops and possible expansion of interseeding these forages into existing pastures. Invited participants will include local ranchers and farmers, local soil and water conservation district members, University Extension professionals, local 4H and FFA groups, local Natural Resources Conservation Services and Farm Service agency personnel, and agricultural business representatives. In addition, Serkan will bring his college students from Oregon State University to participate in the field day.
Year 2: A tour of the project site will occur with follow up panel discussion. The tour will be video taped for future web viewing. The field day will also include a panel discussion on cover crops, grazing, and soil health with information from the project being explained through Power Point and handouts. Our fact sheet will be advertised as work on it will have already begun. Invited participants will include local ranchers and farmers, local soil and water conservation district members, University Extension professionals, local 4H and FFA groups, local Natural Resources Conservation Services and Farm Service agency personnel, and agricultural business representatives, as well as college students from Oregon State University.
Due to Covid-19 in 2020, a field day could not be hosted on site. Instead, a virtual tour and webinar was presented through the western Cover Crops council, Intermountain region. Participants included farmers, ranchers, University faculty, and educators. In 2021, a field day was not possible due to historic drought levels and Lake County highlighted as extremely dry (see attached National Oceanic and Atmospheric drought map). Irrigation water was shut off to our project field and no full irrigation occurred , thereby subjecting the field to undue stress. A field check in May 2021 confirmed no 2020 interseeded forages were present (see picture).
Peer Reviewed Fact Sheet: A peer reviewed fact sheet was prepared by Fara and Serkan in collaboration with Oregon State University's in 2021 highlighting birdsfoot trefoil as a succesfully interseeded forage (attached to this report). Due to historic drought levels in 2021, the other seeded forages could not be evaluated because the field pivot was not operative due to lack of water.
Web based outreach: Project information was highlighted through the newly formed Western Cover Crops council through a webinar and email communication with participants. The factsheet was made available through Oregon State University Extension website and outreach by Extension offices throughout the state
Additionally, this project was highlighted and discussed in an outreach forum through the western Cover Crops council. The project was also presented with forage results through a webinar hosted by the western Cover Crops council, Intermountain region (attached PowerPoint presentation)
Education and Outreach Outcomes
Timing of seeding has been our challenge and opportunity within this project under irrigation. Due to the high degree of variability in this region, early spring planting that would normally occur elsewhere will not work here. Initially, we planted in May and our plots failed due to the high regrowth of the existing perennials in the pasture as well as the cold impact on emerging seedlings. We also fertilized all treatment and control plots in May which further supported the existing cool season perennials. This overwhelming competition from existing pasture compromised sunlight and water from our desired forages. We decided to replant in July. The summer planting brought success for our planted forages but compromised biomass and forage quality due to cold weather in the fall and the short window for growth. If we had planted only two weeks earlier in mid June, we would have maximized potential of our desired planted forages. However, due to time constraints, we had to opt for a July seeding in 2020. Moving forward, we believe timing of seeding has been our biggest learning opportunity within this project.
Unfortunately, due to historic drought in 2021 and lack of irrigation water, we could not evaluate the following year effect by our efforts in 2020. We can visually assess the field if irrigation water is available in 2022, and determine which forage species from 2020 remain in the system.