Developing Corn Silage Systems to Meet the Needs of Cover Crops

Progress report for LNE18-361

Project Type: Research and Education
Funds awarded in 2018: $196,108.00
Projected End Date: 03/31/2021
Grant Recipient: University of Vermont
Region: Northeast
State: Vermont
Project Leader:
Dr. Heather Darby
University of Vermont Extension
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Project Information

Performance Target:

Twenty-five farmers will modify a corn silage practice, improve establishment of a cover crop, improve soil health ratings from medium to high, or report yield increases of 2 tons per acre on 500 acres of corn silage.

Introduction:

Farmers in the Northeast are rapidly adopting cover cropping.  Cover cropping in Vermont alone has increased from 14,000 to 28,000 acres in one year.  Farmers have identified the need to diversify cover crops and want to establish mixtures to address certain issues on their fields.  Nearly all cover crops planted in the northern regions focus on using winter rye as the primary cover.  Farms have noted that this cover crop has limitations with respect to certain issues the farmer may want to address (i.e. nitrogen production) and that it can be difficult to control in the spring.  In order for most farms in northern regions to establish cover crop mixtures, they must interseed the cover crop into standing corn.  New tools exist to interseed the crops similar to planting with a grain drill. Project partners have been successful at acquiring multiple pieces of interseeding equipment to be demonstrated on farms. This includes a PennState Interseeder (Interseeder Technologies, PA), Duo Inter-Seeder (Dawn Biologic, PA), and a High Clearance Cover Crop Interseeder (Haige Inc., IA).  Farmers are excited about this opportunity.  Preliminary work conducted by PI-Darby indicates that standard practices used to grow silage corn may actually reduce the establishment of interseeded cover crops.  To help farmers reap the benefits of diversified cover crop mixtures in the far northern stretches of the northeast, corn silage practices must be altered.  Silage corn is leafy and planted thick to maximize yield and quality of the forage.  Horizontal versus a vertical leaf structure increases shading of the soil reducing the ability of the planted cover crop to establish.  Long season varieties are planted to maximize the yield and growing season.  Many farmers have moved towards narrow row spacing (20 inch rows) reducing the ability of the cover crop to grow.  The use of fixed-ear corn varieties have allowed farmers to plant higher populations without compromising grain development.   Seeding cover crops when the equipment is available instead of seeding when the crop and field conditions are optimum have significant impacts on establishment of interseeded cover crops. Herbicides with residual are used to eliminate weeds in corn but limit cover crop establishment.  All of these practices do not promote growth of interseeded cover crops. Based on current research and farmer needs it is apparent that corn silage production strategies need to be altered to support successful interseeding of cover crops.

The proposed solution

Farmers have demonstrated their desire to cover crop and ability to integrate new practices into their operations. However, cover cropping research has focused largely on the cover crop itself and has neglected to acknowledge other factors in the system; farmers need strategies that encompass the entire production system in order to fully realize the benefits of cover cropping. Therefore, this project seeks to identify corn cropping best practices that result in successful establishment of interseeded cover crops.

Three major factors that need to be balanced in order for interseeding to be successful: corn plant characteristics, agronomics, and environmental conditions. Recent corn variety development has led to numerous varieties with a wide range of characteristics. By assessing the impact of these characteristics (leaf and ear architecture and relative maturity) we can determine optimal characteristics that increase light infiltration through the corn canopy increasing cover crop establishment.

Interseeding cover crops requires adequate soil moisture, light infiltration, and temperature throughout the establishment window. This has become more difficult in the face of increasingly erratic weather. Therefore, this project aims to determine cover crop planting timings which balance the needs of the cover crop with environmental conditions and lead to successful establishment.

Finally, agronomic factors, such as herbicide selection and corn populations, also need to be adapted to support interseeding. Most herbicides used in corn silage systems have long residuals that inhibit the germination and growth of interseeded cover crops. Furthermore, silage corn is traditionally planted around 34,000 seeds/acre. However, yield reductions may not necessarily be seen if variety selection is considered when populations are reduced. Lower plant populations may allow for higher light infiltration and therefore cover crop establishment.

Farmers have a desire to produce high yield/quality crops and want to implement practices that allow for that goal to be achieved at the lowest cost. The rapid expansion of cover cropping indicates that farmers realize that integrating cover crops into their corn silage system can help them achieve their crop production goals through improvements in soil quality and pest management. Information provided to farmers through this research and outreach program will allow farms to establish cover crops that will provide them with the soil, pest, and crop benefits that they desire from the practice of cover cropping. Farmers can expect to see improved cover crops, soil quality, crop yields, and ultimately reduced costs.

Cooperators

Click linked name(s) to expand
  • Richard Kersbergen (Educator and Researcher)
  • Caragh Fitzgerald (Educator and Researcher)
  • Kirsten Workman (Educator and Researcher)

Research

Hypothesis:

We propose that changes in corn silage production practices and cover crop seeding opportunities can improve the establishment of interseeded cover crops.
This improved establishment will lead to greater cover crop biomass, which is known to reduce erosion, improve soil quality, water and nutrient management, weed control and, ultimately, corn silage yields.
We will specifically examine the effects of corn silage seeding rate, corn type (plant architecture), corn relative maturity rating, and interseeding timing on cover crop establishment. Treatments will be evaluated in small plots with on-station trials and across multiple environments with on-farm replicated strip trials.

Materials and methods:

2018 On-Farm Trials

On-farm unified cover crop testing trials

In order to better understand the impact of cover crops on soil health, three fields from three farms were identified that had not been cover cropped.  Soil samples were taken the year of cover crop interseed establishment (Table 1).  The cover crop was a 25 lb mix comprised of 70% annual rye, 20% clover, and 10% radish.

Table 1. Four participating farms’ cover crop interseeded planting date and soil health sampling date.

Farm

Cover crop planting date

Soil health sampling date

Rainville

6/26/2018

6/26/2018

Rowley

6/19/2018

6/26/2018

Vosburg

6/18/2018

6/26/2018

 

Effect of corn architecture, seeding rate, and hybrid

 Field Management Summary – Tom Machia located in St. Albans Bay, VT  

On 23-May, semi-flex ear MY87B10 and flex ear 2G161 Mycogen short season corn varieties were planted at 30,000 and 35,000 plants acre-1 ­in a side by side comparison of no-till and conventional farming practices at the Machia Farm in St. Albans Bay, VT. Nytan was applied at a rate of six gallons acre-1 at time of planting.  There were a total of 3-row 24 plots, three replicates of each variety at each seeding rate.  Due to a planter issue, the conventional field had four replicates of both varieties and 35,000 plants acre-1 and only two replicates of 30,000 plants acre-1.  On 7-May, prior to planting, soil health samples were taken in accordance standards for and submitted for analysis to Cornell’s Comprehensive Assessment of Soil. Corn populations were recorded at harvest on 5-Sep. Refer to Table 2 for a summary of cropping records.                        

Table 2. Summary of cropping records.

Field Operator

T. Machia

Soil Preparation

½ no-till,

½ conventional tillage

Planting Conditions

Good

no-till roller crimped; tilled tilled

Planting Date

23-May

Corn Variety

2G161 (84 RM)

MY87B1(87 RM)0

Seeding Rate

(seeds acre-1)

30,000/35,000

Fertilizer Applied

6 gal

9-18-9

Manure Application

Fall 2017 sand from manure pit (14 ton/acre)

PSNT Results

No-till: 15 ppm

85 lbs of N for 25 T corn

Tilled: 28 ppm

0 lbs N for 25T corn

19-Jun

PSNT Application

No-till: 15 ppm

185 lbs 46-0-0

22-Jun

Tilled: 0 lbs

Herbicide Application

No-Till: 2.5 qt Acuron

1.0 qt RoundUp

Till: 2.7 qt Acuron

21-May

Pesticide Application

None

Cover Crop

25 lbs

Annual rye (70%), clover (20%), radish (10%)

Cover Crop Planting Date

13-Jun

Harvest Date

5-Sep

Yield Tons @35% DM

No-till: 23.5

Conventional: 26.9

 

Effect of corn architecture and population- Rainville Farm in Alburgh, VT

 Field Management Summary 

On 12-Jun, fixed ear MY87B10 and flex ear 2G161 Mycogen short season corn varieties, and fixed ear SW 4029 and flex ear SW 4010 Seedway long season corn varieties were planted at 28, 30, 32, 34, and 36,000 plants acre-1 in a randomized block design with three replicates. Each plot was 10’ x 20’ and consisted of four rows of corn spaced 30” apart. At planting, liquid starter fertilizer (9-18-9) was applied at a rate of 5 gal ac-1. Due to a field management error, the plots containing the short season varieties were replanted on 30-Jun. Cover crops were interseeded into the plots on 5-Jul using a 10’ Penn State interseeder. Beginning on 3-Jul, photosynthetic active radiation (PAR) levels penetrating through the corn canopy to ground level were recorded approximately weekly in all plots until harvest. PAR was measured using a LI-COR LI-191R Line Quantum Sensor equipped with a LI-1500 GPS enabled data logger. In each plot two measurements were taken, one above the corn canopy to capture the total available sunlight, and one under the canopy at approximately ground level in the center of the plot to capture light available to the cover crop. From these two readings percent infiltration of PAR was calculated by dividing the in-canopy reading by the outside reading. Corn was harvested 5-Oct. Yields were recorded using a wagon equipped with scales. An approximate one lb subsample from each plot was collected, weighed, and dried to determine dry matter content at harvest. The dried samples are still in the process of being ground and analyzed for silage quality. Post-harvest, ground cover from the cover crop was recorded using the Canopeo application. The cover crops were too small to collect biomass from at this location. Refer to Table 3 for a summary of cropping records for this trial and location.

Table 3. Summary of cropping records.

Field Operator

R. Rainville

Soil Preparation

Moldboard plow followed by disk and spike tooth harrow

Planting Date

12-Jun, short season plots replanted 30-Jun

Corn Varieties

2G161 (84 RM, flex)

MY87B10 (87 RM, fixed)

SW4010 (100 RM, flex)

SW4029 (100 RM, fixed)

Seeding Rates

(seeds acre-1)

28,000

30,000

32,000

34,000

36,000

Starter Fertilizer

5 gal ac-1 9-18-9 starter

Additional Fertilizer Applied

None

Herbicide Application

None

Pesticide Application

None

Cover Crop

25 lbs ac-1

Annual ryegrass (70%)

Red clover (20%)

Tillage radish (10%)

Cover Crop Planting Date

5-Jul

Harvest Date

5-Oct

Yield Tons ac-1 @35% DM

Trial average: 16.5

 

Effect of corn architecture and interseed timing- Rainville Farm in Alburgh, VT

 Field Management Summary   

On 12-Jun, fixed ear MY87B10 and flex ear 2G161 Mycogen short season corn varieties, and fixed ear SW 4029 and flex ear SW 4010 Seedway long season corn varieties were planted 34,000 seeds acre-1 in a randomized block design with four replicates. Each plot was 10’ x 20’ and consisted of four rows of corn spaced 30” apart. At planting liquid starter fertilizer (9-18-9) was applied at a rate of 5 gal ac-1. Due to a field management error, the plots containing the short season varieties were replanted on 30-Jun. Cover crops were interseeded into the plots at the V2, V4, and V6 growth stages using a 10’ Penn State interseeder. Beginning on 3-Jul, photosynthetic active radiation (PAR) levels penetrating through the corn canopy to ground level was recorded approximately weekly in all plots until right before harvest. PAR was measured using a LI-COR LI-191R Line Quantum Sensor equipped with a LI-1500 GPS enabled data logger. In each plot two readings were taken, one above the corn canopy to capture the total available sunlight, and one under the canopy at approximately ground level in the center of the plot to capture light available to the cover crop. From these two readings percent infiltration of PAR was calculated by dividing the in-canopy reading by the outside reading. Corn was harvested on 4-Oct. Yields were recorded using a wagon equipped with scales. An approximate one lb subsample from each plot was collected, weighed, and dried to determine dry matter content at harvest. The dried samples are still in the process of being ground and analyzed for silage quality. Post-harvest, ground cover from the cover crop was recorded using the Canopeo application. The cover crops were too small to collect biomass from at this location. Refer to Table 4 for a summary of cropping records for this trial and location.

Table 4. Summary of cropping records.

Field Operator

R. Rainville

Soil Preparation

Moldboard plow followed by disk and spike tooth harrow

Planting Date

12-Jun, short season plots replanted 30-Jun

Corn Varieties

2G161 (84 RM, flex)

MY87B10 (87 RM, fixed)

SW4010 (100 RM, flex)

SW4029 (100 RM, fixed)

Interseed Timings (corn growth stages)

V2

V4

V6

Starter Fertilizer

5 gal ac-1 9-18-9 starter

Additional Fertilizer Applied

None

Herbicide Application

None

Pesticide Application

None

Cover Crop

25 lbs ac-1

Annual ryegrass (70%)

Red clover (20%)

Tillage radish (10%)

Cover Crop Planting Dates

2-Jul (V2)

5-Jul (V4)

30-Jul (V6)

Harvest Date

4-Oct

Yield Tons @35% DM

Overall: 18.6

 

Effect of corn architecture, seeding rate, and hybrid – Smith Farm

 Field Management Summary                                  

On 27-Jun, semi-flex ear MY87B10 and flex ear 2G161 Mycogen short season corn varieties were planted at 30,000 and 35,000 plants acre-1. At planting, RiseR (pop-up fertilizer) 7-17-3 was applied through the planter at 5 gallons acre-1.  One hundred lbs acre-1 urea fertilizer (46-0-0) was broadcast into corn just before the cover crop was interseeded.  There were a total of 24 plots, seven  replicates of both varieties and 35,000 plants acre-1 and five replicates of 30,000 plants acre-1.  Each plot was 7.5’ wide, running the length of the field, consisting of three rows of corn. A PSNT soil test was collected on 13-Aug which indicated the need for additional nitrogen.  However, no additional nitrogen fertilizer was applied.  Corn was hand harvested on 12-Oct.  See Table 5 for a summary of field management operations.

Table 5. Summary of cropping records.

Field Operator

P. Smith

Soil Preparation

Disc Harrow twice (fallow/volunteer red clover) the week before planting

Planting Conditions

Dry, but otherwise good

Planting Date

27-Jun

Corn Variety

2G161 (84 RM)

MY87B1(87 RM)

Seeding Rate

(seeds acre-1)

30,000/35,000

Fertilizer Applied

5 gal @ 7-17-3 (27-Jun)

100 lbs @ 46-0-0 (31-Jul)

Manure Application

N/A

PSNT Results

15 ppm

55 lbs of N for 15 T corn

 (13-Aug)

PSNT Application

N/A

Nitrogen applied 31-Jul

 (see above)

Herbicide Application

Corvus @ 4 oz. acre-1

Aatrex @ 1 pt. acre-1

(7-Jul)

Pesticide Application

None

Cover Crop

25 lbs. acre-1

Annual rye (70%), clover (20%), radish (10%)

Cover Crop Planting Date

2-Aug

Harvest Date

12-Oct

Yield Tons @35% DM

13.9 tons acre-1

 

2018 Maine: Interseed Cover Crop On-Farm Research Projects

 Effect of corn seeding rate on cover crop growth – Barker Farm

 Field Management Summary  

On 19-May, short season corn was seeded at 28,000 and 32,000 plants acre-1. There were a total of 16 plots, 5 replicates of each seeding rate. Cover crops were interseeded on 24-Jun (V4) using a farmer-modified Spray Coupe. Light meter readings were recorded on 26-Jun, 4-Jul, 11-Jul, 19-Jul, 30-Jul, 10-Aug, and 8-Sep. Corn was sampled on 9-Sep for analysis.                                 

Table 5. Summary of cropping records.

Field Operator

Barker Farm

Soil Preparation

 

Planting Conditions

 

Planting Date

19-May

Corn Variety

 

Seeding Rate

(seeds acre-1)

28,000/32,000

Fertilizer Applied

 

Manure Application

 

PSNT Results

ppm

lbs of N for T corn

 (13-Aug)

PSNT Application

 

Nitrogen applied 31-Jul

 (see above)

Herbicide Application

Round-Up @ oz. acre-1

Banvel @  pt. acre-1

(7-Jul)

Pesticide Application

None

Cover Crop

15 lbs. acre-1

Annual rye (72%), clover (10%), turnip (10%) radish (7%)

Cover Crop Planting Date

24-Jun

Harvest Date

8-Sep

Yield Tons @35% DM

tons acre-1

 

  Effect of corn plant architecture on cover crop growth – Wright Farm

 Field Management Summary  

In mid-May, short season corn varieties Mycogen MY87B10 and 2G161 were planted as field trials at two locations.  Cover crops were interseeded in late June. Light meter readings were recorded at both locations on 7-Jul, 12-Jul, 20-Jul, 30-Jul, 10-Aug, and 7-Sep. Corn was sampled on 7-Sep for analysis. At Wright Place Farm, cover crop ground cover was measured by Canopeo and samples were collected for dry matter.  Cover crop samples were not measured at Windgate Farm due to uneven soil moisture which resulted in irregular cover crop stand.

Table 6. Summary of cropping records.

Field Operator

Wright Place Farm

 

Soil Preparation

 

 

Planting Conditions

 

 

Planting Date

24-May

20-May

Corn Variety

Mycogen MY87B10/ Mycogen 2G161

Mycogen MY87B10/ Mycogen 2G161

Seeding Rate

(seeds acre-1)

 

 

Fertilizer Applied

 

 

Manure Application

 

 

PSNT Results

ppm

lbs of N for T corn

 

 (13-Aug)

 

PSNT Application

 

 

Nitrogen applied 31-Jul

 (see above)

 

Herbicide Application

Glyphosate and Verdict @ 10oz. acre-1

(27-May)

 

Pesticide Application

None

 

Cover Crop

15 lbs. acre-1

Annual rye (72%), clover (10%), turnip (10%) radish (7%)

15 lbs. acre-1

Annual rye (72%), clover (10%), turnip (10%) radish (7%)

Cover Crop Planting Date

25-Jun

 

Harvest Date

7-Sep

7-Sep

Yield Tons @35% DM

tons acre-1

tons acre-1

 

Effect of interseeding timing on cover crop growth – Barker Farm

Field Management Summary 

Prior to cover crop planting, herbicides Roundup and Banvel were applied.  Cover crops in this field trial were planted on 26-Jun (V4), 7-Jul (V5-6), 9-Jul (V6), and 17-Jul (V7). Light meter readings were recorded on 26-Jun, 4-Jul, 11-Jul, 19-Jul, 30-Jul, 10-Aug, and 8-Sep. Corn was hand-sampled on 8-Sep for analysis. The cover crop ground cover was measured by Canopeo and samples collected for biomass measurements on 25-Sept.                             

Table 7. Summary of cropping records.

Field Operator

Barker Farm

Soil Preparation

 

Planting Conditions

 

Planting Date

 

Corn Variety

 

Seeding Rate

(seeds acre-1)

 

Fertilizer Applied

 

Manure Application

 

PSNT Results

ppm

lbs of N for T corn

 (13-Aug)

PSNT Application

 

Nitrogen applied 31-Jul

 (see above)

Herbicide Application

Round-Up @ oz. acre-1

Banvel @  pt. acre-1

(7-Jul)

Pesticide Application

None

Cover Crop

15 lbs. acre-1

Annual rye (72%), clover (10%), turnip (10%) radish (7%)

Cover Crop Planting Date

25-Jun (V4)

7-Jul (V5-6)

9-Jul (V6)

17-Jul (V7)

Harvest Date

8-Sep

Yield Tons @35% DM

tons acre-1

 

Effect of corn hybrid on cover crop growth – Misty Meadow Farm

Field Management Summary 

On 22-May, 43 corn hybrids were planted in three replicates of 15’X 75’ plots.  On 25-Jun, the cover crop was planted. Prior to cover crop planting, herbicides Roundup and Banvel were applied.  Cover crops in this field trial were planted on 26-Jun (V4), 7-Jul (V5-6), 9-Jul (V6), and 17-Jul (V7). Light meter readings were planned to be measured during the trial.  There was no light interception during the first reading and it was impossible to access the plots in subsequent attempts due to size of the trial.  At the end of the season, cover crop stands were very irregular within each plot and varied greatly from plot to plot.  For this reason, cover crop measurements were not taken.                              

Table 8. Summary of cropping records.

Field Operator

Misty Meadow Farm

Soil Preparation

 

Planting Conditions

 

Planting Date

22-May

Corn Variety

43 hybrids

Seeding Rate

(seeds acre-1)

 

Fertilizer Applied

125 lbs acre-1 N as urea

(preplant)

Manure Application

5,000 gal acre-1

PSNT Results

ppm

lbs of N for T corn

 (13-Aug)

PSNT Application

 

Nitrogen applied 31-Jul

 (see above)

Herbicide Application

Glyphosate and Verdict @ 10 oz. acre-1

(pre-emergence)

Pesticide Application

None

Cover Crop

15 lbs. acre-1

Annual rye (72%), clover (10%), turnip (10%) radish (7%)

Cover Crop Planting Date

25-Jun

Harvest Date

13-Sep

   

On 22-May, 43 corn hybrids were planted in three replicates of 15’X 75’ plots.  On 25-Jun, the cover crop was planted. Prior to cover crop planting, herbicides Roundup and Banvel were applied.  Cover crops in this field trial were planted on 26-Jun (V4), 7-Jul (V5-6), 9-Jul (V6), and 17-Jul (V7). Light meter readings were planned to be measured during the trial.  There was no light interception during the first reading and it was impossible to access the plots in subsequent attempts due to size of the trial.  At the end of the season, cover crop stands were very irregular within each plot and varied greatly from plot to plot.  For this reason, cover crop measurements were not taken.

2019 Unified Farm Trials

On-farm unified cover crop testing trials

In order to better understand the impact of cover crops on soil health, three fields from three farms were identified that had not been cover cropped.  Soil samples were taken the year of cover crop interseed establishment (Table 9).  The cover crop was a 25 lb mix comprised of 70% annual rye, 20% clover, and 10% radish.

Table 9. Three participating farms’ cover crop interseeded planting date and soil health sampling date.

Farm

Cover crop planting date

Cover crop planting date

Soil health sampling date

Rainville

7/10

6/26/2018

6/26/2018

Rowley

n/a*

6/19/2018

6/26/2018

Vosburg

7/15

6/18/2018

6/26/2018

*Rowley seeded corn fields into hayland.

 

Effect of corn architecture, seeding rate, and hybrid

Field Management Summary                        

Table 9. Summary of cropping records at T. Machia.

Field Operator

T. Machia

Soil Preparation

½ no-till,

½ conventional tillage

Planting Conditions

Good

no-till roller crimped;

tilled tilled

Planting Date

30-May

Corn Variety

TMF2Q419 (96 RM, semi-flex, horizontal)

TMF2L395 (94 RM, semi-flex, vertical)

Seeding Rate

(seeds acre-1)

30,000/35,000

Fertilizer Applied

5 gal

9-18-9

Manure Application

Fall 2018 sand from manure pit (14 ton/acre)

PSNT Results

No-till: 5 ppm

140 lbs of N for 25 T corn

Tilled: 10 ppm

115 lbs N for 25T corn

1-Jul

PSNT Application

No-till: 0 lbs

Tilled: 0 lbs

Herbicide Application

2.5 qt. Acuron

Pesticide Application

None

Cover Crop

25 lbs

Annual rye (70%), clover (20%), radish (10%)

Cover Crop Planting Date

28-Jun

Harvest Date

30-Sep

Yield Tons @35% DM

No-till: 16.9

Conventional: 17.5

On 30-May, horizontal-leaf architecture TMF2Q419 and vertical-leaf architecture TMF2L395 Mycogen short season corn varieties were planted at 30,000 and 35,000 plants acre-1 ­in a side by side comparison of no-till and conventional farming practices (See Appendix A for plot map). Nytan was applied at a rate of five gallons acre-1 at time of planting.  There were a total of 3-row 24 plots, three replicates of each variety at each seeding rate.  PSNT samples were taken on 1-Jul.  No sidedress nitrogen was added. Corn populations were recorded at harvest on 30-Sep. Refer to Table 10 for a summary of cropping records.

2019 Effect of corn architecture and population- Rainville location

Field Management Summary                               

Table 10. Summary of cropping records at R. Rainville.

Field Operator

R. Rainville

Soil Preparation

Moldboard plow followed by disk and spike tooth harrow

Planting Date

5/23/2019

Corn Varieties

TMF2Q419 (96 RM, semi-flex, horizontal)

TMF2L395 (94 RM, semi-flex, vertical)

SW4010 (100 RM, flex, horizontal)

SW4029 (100 RM, fixed, vertical)

Seeding Rates

(seeds acre-1)

28,000

30,000

32,000

34,000

36,000

Starter Fertilizer

5 gal ac-1 9-18-9 starter

Additional Fertilizer Applied

513 lbs ac-1 28-0-0 applied

6-29-19

Herbicide Application

1 qt ac-1 Roundup Power Max 6/10/2019

Pesticide Application

None

Cover Crop

25 lbs ac-1

Annual ryegrass (70%)

Red clover (20%)

Tillage radish (10%)

Cover Crop Planting Date

7/1/2019

Harvest Dates

9/27/2019 (short RMs)

10/9/2019 (long RMs)

Yield Tons ac-1 @35% DM

Trial average: 25.2

On 23-May, semi-flex ear, vertical-leaf architecture TMF2L395 and flex ear, horizontal-leaf architecture TMF2Q419 Mycogen short season corn varieties, and fixed ear, vertical-leaf architecture SW 4029 and flex ear, horizontal-leaf architecture SW 4010 Seedway long season corn varieties were planted at 28, 30, 32, 34, and 36,000 plants acre-1 in a randomized block design with four replicates. Each plot was 10’ x 20’ and consisted of four rows of corn spaced 30” apart. At planting liquid starter fertilizer (9-18-9) was applied at a rate of 5 gal ac-1. Cover crops were interseeded into the plots on 1-Jul using a 10’ Penn State interseeder. Beginning 2-Jul, photosynthetic active radiation (PAR) levels penetrating through the corn canopy to ground level was recorded approximately weekly in all plots until right before harvest. PAR was measured using a LI-COR LI-191R Line Quantum Sensor equipped with a LI-1500 GPS enabled data logger. In each plot two readings were taken, one above the corn canopy to capture the total available sunlight, and one under the canopy at approximately ground level in the center of the plot to capture light available to the cover crop. From these two readings percent infiltration of PAR was calculated by dividing the in-canopy reading by the outside reading. Short season varieties were harvested on 27-Sep and long season varieties on 9-Oct. Yields were recorded using a wagon equipped with scales. An approximate 1 lb subsample from each plot was collected, weighed, and dried to determine dry matter content at harvest. The dried samples are still in the process of being ground and analyzed for silage quality. Post-harvest, ground cover from the cover crop was recorded using the Canopeo application on 6-Nov. The cover crops were too small to collect biomass from at this location. Refer to Table 7 for a summary of cropping records for this trial and location. Although statistical analysis has not yet been completed for this location, some preliminary differences were seen between treatments.

2019 Effect of corn architecture and interseed timing- Rainville location

Field Management Summary                                

Table 10. Summary of cropping records at R. Rainville.

Field Operator

R. Rainville

Soil Preparation

Moldboard plow followed by disk and spike tooth harrow

Planting Date

23-May

Corn Varieties

TMF2Q419 (96 RM, semi-flex, horizontal)

TMF2L395 (94 RM, semi-flex, vertical)

SW4010 (100 RM, flex, horizontal)

SW4029 (100 RM, fixed, vertical)

Interseed Timings (corn growth stages)

V2

V4

V6

Starter Fertilizer

5 gal ac-1 9-18-9 starter

Additional Fertilizer Applied

513 lbs ac-1 28-0-0 applied

6-29-19

Herbicide Application

1 qt ac-1 Roundup Power Max 6/10/2019

Pesticide Application

None

Cover Crop

25 lbs ac-1

Annual ryegrass (70%)

Red clover (20%)

Tillage radish (10%)

Cover Crop Planting Dates

6-17-18 (V2)

6-24-18 (V4)

7-1-18 (V6)

Harvest Dates

9/23/2019 (short RMs)

10/10/2019 (long RMs)

Yield Tons @35% DM

Overall: 21.6

On 23-May, fixed ear TMF2L395 and flex ear TMF2Q419 Mycogen short season corn varieties, and fixed ear SW 4029 and flex ear SW 4010 Seedway long season corn varieties were planted at 34,000 seeds acre-1 in a randomized block design with four replicates. Each plot was 10’ x 20’ and consisted of four rows of corn spaced 30” apart. At planting liquid starter fertilizer (9-18-9) was applied at a rate of 5 gal ac-1. Cover crops were interseeded into the plots at the V2, V4, and V6 growth stages using a 10’ Penn State interseeder. Beginning 19-Jun, PAR levels penetrating through the corn canopy to ground level was recorded approximately weekly in all plots until right before harvest. PAR was measured using a LI-COR LI-191R Line Quantum Sensor equipped with a LI-1500 GPS enabled data logger. In each plot two readings were taken, one above the corn canopy to capture the total available sunlight, and one under the canopy at approximately ground level in the center of the plot to capture light available to the cover crop. From these two readings percent infiltration of PAR was calculated by dividing the in-canopy reading by the outside reading. Short season varieties were harvested on 23-Sep and long season varieties were harvested on 10-Oct. Yields were recorded using a wagon equipped with scales. An approximate 1 lb subsample from each plot was collected, weighed, and dried to determine dry matter content at harvest. The dried samples are still in the process of being ground and analyzed for silage quality. Post-harvest, plots were too weedy to capture ground cover from the cover crop as was measured in the population trial. Refer to Table 10 for a summary of cropping records for this trial and location. Although statistical analysis has not yet been completed for this location, some preliminary differences were seen between treatments.

2019 Effect of corn architecture, seeding rate, and hybrid – Foster Farm

Field Management Summary                                  

Table 12. Summary of cropping records at G. Foster.

Field Operator

G. Foster

Soil Preparation

No-Till

Winter Rye Cover Crop rolled/crimped after planting

Planting Conditions

wet

Planting Date

06/20/2019

Corn Variety

TMF2L395 (94 RM) – vertical

TMF2Q419 (96 RM) – horizontal

Seeding Rate

(seeds acre-1)

30,000/35,000

Fertilizer Applied

10 gal @ 32-0-0  (06/20/19)

200 lbs @ 46-0-0 (07/26/19)

Manure Application

N/A

Herbicide Application

Anthem MAXX @ 3 oz. acre-1

Roundup @ 1 at. acre-1

Hellfire (adjuvant) and Clasp (drift retardant)

(6/23/2019)

Pesticide Application

None

Cover Crop

35 lbs. acre-1

Annual rye (73%), clover (20%), radish (5%)

Total Pure Live Seed rate = 31 lbs  acre-1

Cover Crop Planting Date

07/22/2019

Harvest Date

10/10/2019

Yield Tons @35% DM

14.5 tons acre-1

On June 27th, vertical-leaf architecture TMF2L395 and horizontal-leaf architecture TMF2Q419 Mycogen moderate length season corn hybrids were planted at 30,000 and 35,000 plants acre-1. UAN (Urea-ammonium nitrate) 32-0-0 was applied through the planter at 10 gallons acre-1. 200 pounds acre-1 Urea (46-0-0) was applied as side dress in late July.  There were a total of 12 6-row, 30-inch plots that were 515-feet in length.  This was comprised of three replicates of each hybrid at 30,000 plants acre-1 and 35,000 plants acre-1 (Table 12). Cover crop was interseeded into all plots on July 22, 2019 with an interseeder drill.  A mixture of 73.43% Annual Ryegrass/19.99% medium red clover/4.98% forage radish by weight was seeded at 35 pounds acre-1 , which equaled a pure live seed rate of 31 pounds acre-1  Cover crop had good germination of all species, and grew well throughout the season. Corn was hand harvested on October 10th, 2019 to match the farmer’s harvest schedule. Cover crop establishment was measured by collecting percent cover and biomass samples at harvest and three weeks post-harvest on all plots.

Maine Trials

Effect of corn seeding rate on cover crop growth – Leeds Farm

Field Management Summary                                  

Table 13. Summary of cropping records at Barker Farm.

Field Operator

Barker Farm

Soil Preparation

 

Planting Conditions

 

Planting Date

12-Jul

Corn Variety

 

Seeding Rate

(seeds acre-1)

28,000/32,000

Fertilizer Applied

 

Manure Application

 

PSNT Results

 

 

PSNT Application

 

Herbicide Application

 

Pesticide Application

None

Cover Crop

15 lbs. acre-1

Annual rye (80%), medium red clover (10%), purple top turnip (5%) Eco-till radish (5%)

Cover Crop Planting Date

22-Jul

Harvest Date

 

Yield Tons @35% DM

n/a

On 12-Jul, short season corn was seeded at 28,000 and 32,000 plants acre-1. There were a total of 16 plots, 5 replicates of each seeding rate. Cover crops were interseeded on 22-Jul using a farmer-modified Spray Coupe. Light meter readings were recorded on 26-Jun, 4-Jul, 11-Jul, 19-Jul, 30-Jul, 10-Aug, and 8-Sep. Corn was sampled on 9-Sep for analysis (Table 13).

A wet spring resulted in extremely late planting and the growing season was very compressed.  By the time a suitable waiting period passed after herbicide application, there was only time for one overseeding before the corn was too tall (>6’ tall) for the equipment.

With only one overseeding date and no comparisons to be made, yield data was not collected on this plot in 2019.  After harvest, no significant cover crop could be found in the plot. 

 Effect of corn hybrid on cover crop growth – Misty Meadow Farm

Field Management Summary                                        

Table 14. Summary of cropping records at Misty Meadow Farm.

Field Operator

Misty Meadow Farm

Soil Preparation

 

Planting Conditions

 

Planting Date

3-June

Corn Variety

39 hybrids

Seeding Rate

(seeds acre-1)

32,000

Fertilizer Applied

 

Manure Application

 

PSNT Results

 

PSNT Application

75 lbs acre-1  nitrogen on 31-Jul

Herbicide Application

Verdict pre-emergence, Spirit post-emergence

Pesticide Application

None

Cover Crop

15 lbs. acre-1

Annual ryegrass (80%), medium red clover (10%), purple-top turnip (5%), and Eco-till radish (5%). 

Cover Crop Planting Date

10-Jul

Harvest Date

16-Oct

Average Yield Tons @35% DM

17.4 tons acre-1

On 3-June, 39 corn hybrids were planted in three replicates of 15’X 75’ plots (Table 13). On 10-July, the cover crop was planted. Prior to cover crop planting, herbicides Verdict and Spirit were applied. Cover crop emergence was limited and spotty under the canopy. There was little cover visible after harvest.  It is worth noting that one side of the field was chopped in mid-August in advance of the Farm Days event.  Where the corn was removed early, there was a substantial cover crop stand.

Effect of corn population on cover crop growth

Due to the very wet early-summer weather and extremely delayed planting in the region, we were not able to coordinate getting these plots planted. 

Effect of corn plant architecture on cover crop growth

Seed was not received for this trial. 

2020 Trials

The field trials were conducted at Borderview Research Farm in Alburgh, VT (Tables 1 and 2). Trial 1 evaluated the impact of corn variety and population on cover crop establishment and corn yields. Trial 2 evaluated the impact interseed timing on cover crop establishment and corn yields. All plots were 10’ x 20’, consisting of four rows of corn spaced 30” apart, and replicated three times.

The experimental design for Trial 1 was a randomized complete block with split plot design. Main plots were corn population (28,000, 34,000, and 38,000 plants ac-1) and split plots were corn varieties. The plots were interseeded with a cover crop mixture of annual ryegrass (60%), tillage radish (10%) and red clover (30%) when the corn reached the V6 growth stage. In Trial 2, the experimental design was a randomized complete block design where treatments were interseed timing (V2, V4, and V6 corn growth stages).

Corn was planted on 13-May and 6-May in Trial 1 and 2 respectively. In Trial 1, plots were originally seeded at 40,000 seeds ac-1 and thinned to the appropriate treatment populations on 9-Jun. The amount of PAR reaching the ground under the corn canopy was measured using a LI-COR LI-191R line quantum light sensor equipped with a LI-1500 data logger. Light was measured approximately weekly from the time of interseeding through August. To understand how much the corn canopy was obstructing the total available light, a light measurement was taken outside of the corn canopy and then under the corn canopy in the center of each plot. The data were then used to calculate the percent of light infiltrating the corn canopy. Corn was harvested using a John Deere 2-row corn chopper and collected in a wagon fitted with scales to weigh the yield of each plot. An approximate 1 lb subsample was collected, weighed, dried, and weighed again to determine dry matter content and calculate yield. The samples from Trial 1 were then ground to 2mm using a Wiley sample mill and then to 1mm using a cyclone sample mill (UDY Corporation). The samples were analyzed for forage quality via Near Infrared Reflectance Spectroscopy at the UVM Cereal Grain Testing Laboratory (Burlington, VT) using a FOSS DS2500 NIRS. No quality analyses were conducted on the corn from Trial 2.

Following harvest, on 20-Oct, ground cover was measured in Trial 1 by processing photographs using the Canopeo© smartphone application. On 27-Oct, cover crop biomass was measured by collecting biomass within a 0.25m2 area in each plot in the trial. Samples were weighed and dried to determine dry matter content and calculate yield. The samples were also ground using the same procedures for the corn samples and analyzed for %C, %N, and C:N ratio at the University of Vermont Agricultural and Environmental Testing Laboratory (Burlington, Vermont). In Trial 2, cover crop establishment and growth post-harvest was minimal with higher weed incidence than in Trial 1. In order to capture the ground cover contributed by cover crops and weeds separately, ground cover in this trial was measured using the beaded string method on 28-Sep. Cover crops were too small to collect biomass samples and therefore, yield and quality is not reported.

Table 1. Trial corn population by corn variety, Alburgh, VT, 2020.

Location

Borderview Research Farm – Alburgh, VT

Soil type

Cabot extremely stony fine sandy loam

Corn variety treatments

(relative maturity)

B94T73R (94RM)

B94T73SX (94 RM)

B97T04SXE (97 RM)

CP3499VT2P (94 RM)

P9608R (96 RM)

SW3768 (95 RM)

SW4010 (100 RM)

38N85 (92 RM)

9070AM (90 RM)

Corn population treatments

(plants ac-1)

28,000

34,000

38,000

13-May

Corn planting date

Cover crop mixture

25 lbs ac-1

Annual ryegrass (60%)

Red clover (30%)

Tillage radish (10%)

Cover crop planting date

22-Jun

Harvest date

17-Sep

 

Table 2. Trial interseeding timing management, Alburgh, VT, 2020.

Location

Borderview Research Farm – Alburgh, VT

Soil type

Cabot extremely stony fine sandy loam

Interseed timing treatments

(dates of interseeding)

V2 (2-Jun)

V4 (10-Jun)

V6 (22-Jun)

Corn planting date

6-May

Cover crop mixture

25 lbs ac-1

Annual ryegrass (60%)

Red clover (30%)

Tillage radish (10%)

Harvest date

9-Sep

Data were analyzed using mixed model analysis using the mixed procedure of SAS (SAS Institute, 1999).  Replications in the trial were treated as random effects and treatments were treated as fixed. Mean comparisons were made using the Tukey-Kramer adjustment procedure when the F-test was considered significant (p<0.10). Because few significant interactions were observed between year and other variables, data were combined across years prior to the employing the mean comparisons procedure.

Research results and discussion:

Effect of corn architecture, seeding rate, and hybrid – 2018

 Corn Populations and Yield – Tom Machia located in St. Albans Bay, VT   

Overall, the conventional field had 2,000 more plants ac-1 than the no-till field (Table 14).  Plant populations in the lower seeding rate were an average 3,000 plants ac-1 below the seeding rate and the plant populations in the higher seeding rate were an average of 3,600 plants ac-1 below the seeding rate.  However, this variation in plant population, regardless of hybrid or seeding rate did not appear in the yield.  Yields ranged between 26.2 and 27.8 tons ac-1.

 On average, the conventional field yield was 3.4 tons ac-1 more than the no-till field. In the no-till field, plant populations in the lower seeding rate were an average 3,000 plants ac-1 below the seeding rate and the plant populations in the higher seeding rate were an average of 7,200 plants ac-1 below the seeding rate.  In the no-till field, the higher seeding rate of the MY87B10 was 4.2 tons ac-1 higher than the average no-till yield and had yields on par with the average conventional field yield.  However, this variation in plant population, regardless of hybrid or seeding rate did not appear in the yield.  Yields ranged between 26.2 and 27.8 tons ac-1.

This results indicate that hybrid selection or seeding rates may have a bigger impact on yield in no-till fields than conventionally managed fields.

Table 14. Plant populations and yields of hybrids and seeding rate on conventional field.

Management

Hybrid

Seeding Rate

Plant Population

Yield 35% DM

 

 

plants ac-1

plants ac-1

tons ac-1

Conventional

2G161

30,000

26,500

27.8

Conventional

2G161

35,000

30,500

27.4

Conventional

MY87B10

30,000

27,500

26.2

Conventional

MY87B10

35,000

32,250

26.3

 

 

 

Average

26.9

The top performer for a category is highlighted in bold.

Table 15. Plant populations and yields of hybrids and seeding rate on no-till field.

Management

Hybrid

Seeding Rate

Plant Population

Yield 35% DM

 

 

plants ac-1

plants ac-1

tons ac-1

No-till

2G161

30,000

26,700

22.4

No-till

2G161

35,000

25,300

22.5

No-till

MY87B10

30,000

27,300

21.4

No-till

MY87B10

35,000

30,300

27.7

 

 

 

Average

23.5

The top performer for a category is highlighted in bold.

Cover Crop and Weed Populations
Cover crop germination was not uniform in mid-October. To more accurately capture cover crop establishment success, cover crop and weed populations were counted using the beaded string method, as opposed to randomly selecting locations to sample for biomass. On 17-Oct, populations were counted on five 10-foot lengths in each of the 24 plots.

Overall, conventional and no-till systems had negligible differences in percent cover crop establishment.  The no-till field had more weeds, mostly barnyard grass, than the conventional field. Cover crop coverage was 14% greater in the lower seeding rate than the higher seeding rate. This may be due to less competition for sun, moisture, and soil nutrients.  There was an equal amount of weeds at either rate.  There was an 8% higher cover crop establishment success in 2G161 plots than MY87B10 plots.  Cover crop coverage was highest (46%) in the no-till, 2G161 low seeding rate plots and lowest (12%) in the conventional, MY87B10 high seeding rate plots. 

Table 16. Corn and weed populations measured with the beaded string method.

Management

Cover Crop

Weeds

 

%

%

Conventional

29

0

No-Till

31

3

30,000 rate

38

2

35,000 rate

24

2

2G161

34

2

MY87B10

26

1

The top performer for a category is highlighted in bold.

Effect of corn architecture and population- Rainville Farm in Alburgh, VT

Although statistical analysis has not yet been completed for this location, some unexpected differences were seen between treatments. Table 12 below shows the average yields of the different seeding rates for each variable. Overall, fixed ear had higher yields than flex ear and long season outperformed short season. As weather conditions were favorable throughout the season and into the fall, we observed approximately 2.5 tons ac-1 higher yields from long season varieties as short season varieties. However, it is important to recognize that the short season plots also required replanting and therefore were approximately 2 weeks behind the long season plots.  Figure 1 shows the average yield across populations for fixed and flex ear varieties. For the most part yields were similar between the two ear types at the various populations, except for 34,000 plants ac-1 in which the fixed ear plots yielded over 3 tons ac-1 more than the flex ear plots at this population.

Optimal seeding rate for fixed ear was 34,000 plants acre-1 and optimal seeding rate for flex ear was 32,000 plants acre-1.  Regardless of ear type, seeding rates at 36,000 plants acre-1 had yields similar to seeding at 30,000 plants acre-1.  The optimal seeding rate for long season corn was 32,000 plants acre-1 and the optimal seeding rate for short season was 34,000 plants acre-1

Table 17. Yields across treatments.

Population

Average Yield at 35% DM (tons ac-1)

Overall

Fixed ear

Flex ear

Long season

Short season

28,000

14.1

14.3

13.9

15.3

12.9

30,000

16.3

16.5

16.1

17.4

15.2

32,000

17.9

17.9

17.8

20.9

14.8

34,000

18.1

19.7

16.6

18.0

18.3

36,000

16.2

16.3

16.1

18.6

13.8

The top performer for a category is highlighted in bold.

This project also sought to assess potential cover crop establishment differences at different corn seeding rates. Establishment of interseeded cover crop can be impeded by the corn canopy reducing photosynthesis by shading the cover crop.  The percent of PAR light infiltrating through the crop canopy across the season is shown in Figure 2.  Although not analyzed statistically, it appears that more light is available longer at a seeding rate of 32,000 plants acre-1.

Effect of corn architecture and interseed timing- Rainville Farm in Alburgh, VT

Although statistical analysis has not yet been completed for this location, some unexpected differences were seen between treatments. Table 18 below shows the average yields for each of the variables by corn stage at cover crop planting. Overall, regardless of ear team or relative maturity of corn, yields were highest when the cover crop interseeded at the V4 stage.  However, contrary to the previous study (assessing populations), the flex ear corn had higher yields than the fixed ear. Similarly to the previous study (assessing populations), the long season corn had higher yields than the short season corn.

Table 18. Yields across treatments.

Interseed Timing

Average Yield at 35% DM (tons ac-1)

Overall

Fixed ear

Flex ear

Long season

Short season

V2

18.6

17.6

19.5

22.0

15.1

V4

19.6

18.1

21.1

22.9

16.3

V6

17.6

18.1

17.0

20.0

15.1

The top performer for a category is highlighted in bold.

The other aspect of this project is whether these potential yield differences across populations influences cover crop establishment. One way to assess this is by measuring the amount of light available to the emerging cover crop during each corn stage of cover crop interseeding. The percent of PAR light infiltrating through the crop canopy across the season is shown in Figure 4. The timings of the various growth stages that were interseeded at are pointed out on the figure. Interseeding at V2 or V4 allowed emerging cover crop seed to have access to virtually 100% of the total available PAR whereas by V6, the corn canopy was obstructing about 70% of the available light, leaving only 30% for the cover crop to emerge and establish with.

Effect of corn architecture, seeding rate, and hybrid – Smith Farm

Corn Populations and Yield

Overall, yields seemed to be correlated to population more than hybrid at this location (Table 19).  Late planting, heavy clay soil and dry weather combined for a low overall yield average of all plots of 13.9 tons acre-1 (adjusted to 35 percent dry matter values).  At the higher seeding rates yields were 0.7 tons acre-1 higher with the MY87B10 variety.  At the lower seeding rate, yields were 0.6 tons acre-1 higher with the 1G161 variety.

One item of note was that the ear to stalk ratio seemed consistently high, with all treatments ≥ 1.0.  So while overall yields were low, potential feed value could be high.

Table 19. Plant populations and yields of hybrids and seeding rate

Hybrid

Seeding Rate

Plant Population @ V4±

Plant Population @ HarvestII

Yield 35% DM

Ear to Stalk Ratio

 

plants ac-1

plants ac-1

plants ac-1

tons ac-1

 

2G161

30,000

27,533

27,800

12.9

1.1

2G161

35,000

30,762

32,667

14.6

1.0

MY87B10

30,000

28,333

28,000

12.3

1.0

MY87B10

35,000

32,095

34,667

15.3

1.0

 

 

 

Average

13.9

 

             

The top performer for a category is highlighted in bold.

± collected on 31-Jul, measured using 3 x 1/1000th acre population counts in each plot

Π collected on 12-Oct, measured by counting plants harvested using 1 x 1/1000th acre sample in each plot

Cover Crop Populations
Cover crop germination was fairly uniform, other than where there was heavier weed pressure in specific areas in individual plots (Image-1-Interseeding-Cover-Crops). All three species (annual ryegrass, radish, red clover) were observed to have germinated.  However, the red clover seemed to be the least successful overall.  Cover crop establishment was quantified during the corn growing season by using the Canopeo ‘fractional green canopy cover’ measurement using a smartphone app roughly every two weeks up until harvest.  Post-harvest weather quickly turned snowy and we were unable to capture a post-harvest measurement using this method.  To align with the other sites, we collected percent cover using the beaded string method, as opposed to randomly selecting locations to sample for biomass for our final measurement. On 20-Dec, populations were counted on three 10-foot lengths in each of the 24 plots.  Because of previous cold weather, weeds were not counted, and total cover generally went down as much of the cover crop had gone dormant and/or been winter-killed (radish).  However, dead cover crop residue was quantified at this sample date.

Overall, the 2G161 variety consistently had more cover throughout the season the than MY87B10 variety (Table 20).  Early in the season, there was higher percent cover in the higher seeding rate treatments, with some catch up of cover crop in the lower seeding rate before harvest.  However, at the end of the season, there was negligible difference among corn seeding rate treatments of percent cover crop cover.

Table 20. Plant populations and yields of hybrids and seeding rate

Management

Cover Crop

% cover

 

 

8/13/18II

8/29/18 II

9/12/18 II

9/25/18 II

12/20/18±

30,000 rate

5.0

9.9

15.1

26.8

21.3

35,000 rate

5.2

12.9

12.2

18.7

23.3

2G161

5.1

13.1

14.7

26.8

23.9

MY87B10

5.0

9.7

11.6

15.9

20.6

2G161 @ 30,000 rate

5.7

11.2

18.8

33.7

23.3

2G161 @ 35,000 rate

4.7

14.5

11.8

23.4

24.3

MY87B10 @ 30,000 rate

4.3

8.6

11.4

19.8

19.3

MY87B10 @ 35,000 rate

5.6

10.5

11.8

14.0

21.4

The top performer for a category is highlighted in bold.

Π measured using Canopeo digital fractional green canopy cover measurement

± measured using beaded string method

2018 Maine: Initial results

The timing trial consisted of four overseeding dates at approximately weekly intervals, starting 6/24.  Only the cover crop planted at the first seeding date (6/24, at V4) was successful.  We considered the following reasons for the failure of later seedings:

  1. Herbicides with low residual activity were used.  Even so, injury can sometimes occur.  However, since the initial seeding was successful, herbicide injury does not seem a likely cause. 
  2. Within four days of the first seeding, 0.71” of rain fell.  Within five days of the second seeding, 0.43” of rain fell.  Insufficient moisture would not seem to be a likely cause, given this rainfall. 
  3. We know, of course, that the amount of light penetrating the crop canopy will decline as the corn crop grows.  Figure 5 shows the percent of ambient light penetrating the corn canopy at each measurement date.  (The results are from three readings per plot, averaged across all plots.)  At the time of the first overseeding, 98% of the ambient light reached the ground between the corn rows.  By the second overseeding date one week later, only 62% of the light reached the ground.   By the third overseeding date (two weeks after the first), only 36% of light reached the ground between the corn rows.  Although we cannot be certain, we suspect that insufficient light was the reason for the failure of later interseedings.

The timing trial and the flex/semi-flex trial in Burnham were the two trials with measurable cover crop after harvest.  Figure 6 shows the biomass yield and distribution of plant types for the four V4 interseedings of the timing trial and for the flex/semi-flex treatments in Burnham.  Cover crop yield ranged from 1650 lbs dry matter per acre to 371 lbs dry matter per acre.  In all plots, the brassicas dominated the stand.  This was a particular concern to one cooperating farmer, who observed that the brassicas created slippery driving conditions for trucks during the silage harvest.  It also means that there would be few living plants the following spring, since the brassicas are not winter-hardy.  For 2019, we will likely reduce the amount of brassicas in the mix.

2019 Trial Results

Unified On-Farm Trials

On 5-Nov, cover crop biomass was sampled in three 0.25 meter-1 quadrants in each field.  The cover crop samples were tried and results are reported on a dry matter (DM) basis (Table 21). At Rainville’s Rice Hill, radish established well and averaged 700 lbs acre biomass. However, at Vosburg’s farm, rye provided more biomass on most fields. It should be noted that rye percent dry matter was 4-11% higher than that of the radish. Although rye may provide more biomass, the radish leaves covered more surface area, protecting the ground from erosion. 

Table 21. Cover crop biomass.

Farm

Field

Rye

(DM lbs acre-1)

Radish

(DM lbs acre-1)

Clover

(DM lbs acre-1)

Cover Crop Total

(DM lbs acre-1)

Weeds

(DM lbs acre-1)

Rainville

Rice Hill

4.52

700

0.20

705

0.11

Vosburg

Hill

17.8

0

0

17.80

0

Vosburg

By Mark’s

71.4

101

0.04

173

0

Vosburg

Nice

75.8

2.69

0.18

78.7

5.35

Vosburg

Wet

150

41.6

0.24

192

0

 

Effect of corn architecture, seeding rate, and hybrid – Tom Machia

Corn Populations and Yield

In 2018, the conventional field had 2,000 more plants ac-1 than the no-till field.  However, in 2019, the no-till field had 1,750 more plants ac-1 than the conventional field (Tables 22 and 23).  Plant populations in the lower seeding rate were an average 4,083 plants ac-1 below the seeding rate and the plant populations in the higher seeding rate were an average of 5,167 plants ac-1 below the seeding rate.  In the conventional system, plant populations seem to correlate with yield i.e. the higher planting population had higher yields, regardless of variety. In the no-till field, the highest seeding rate had the highest plant population, but not the highest yield.

Yields ranged between 16.3 and 18.6 tons ac-1. On average, the conventional field yield had 0.6 tons ac-1 more than the no-till field. In the conventional field, yields were highest in the higher seeding rate, regardless of corn variety.  In the no-till field, the lower seeding rate had the highest yield, regardless of corn variety. The conventional system had 1.9 more tons ac-1 then the no-till field at the higher seeding rate. The no-till system had 0.8 more tons ac-1 than the conventional field at the lower seeding rate.

Regardless of the tillage system, the TMF2Q419 variety had the highest yield.  On average, TMF2Q419 variety had 0.8 tons ac-1 more than the TMF2L395 variety. However, the seeding rate impacted the performance of the TMF2Q419, depending on the tillage system. In the conventional system the TMF2Q419 variety at the higher seeding rate that had the highest yield, but in the no-till system the TMF2Q419 variety at the lower seeding rate had the highest yield. The difference between the two highest yielding plots, at 0.5 tons ac-1, is negligible.

In 2018, the results indicated that hybrid selection or seeding rates may have a bigger impact on yield in no-till fields than in conventionally managed fields. In 2019, yields seem to be driven by seeding rate.  In the no-til system, lower seeding rates produced higher yields in both varieties. In the conventional system, the highest seeding rates produced the higher yields.

Table 22. Plant populations and yields of hybrids and seeding rate on conventional field.

Management

Hybrid

Seeding Rate

Plant Population

Yield 35% DM

 

 

plants ac-1

plants ac-1

tons ac-1

Conventional

TMF2Q419

30,000

25,333

17.3

Conventional

TMF2Q419

35,000

30,000

18.6

Conventional

TMF2L395

30,000

24,667

16.1

Conventional

TMF2L395

35,000

28,000

17.9

 

 

Average

27,000

17.5

The top performer for a category is highlighted in bold.

 

Table 23. Plant populations and yields of hybrids and seeding rate on no-till field.

Management

Hybrid

Seeding Rate

Plant Population

Yield 35% DM

 

 

plants ac-1

plants ac-1

tons ac-1

No-till

TMF2Q419

30,000

27,000

18.1

No-till

TMF2Q419

35,000

30,667

16.3

No-till

TMF2L395

30,000

26,667

16.8

No-till

TMF2L395

35,000

30,667

16.3

 

 

Average

28,750

16.9

The top performer for a category is highlighted in bold.

Cover Crop and Weed Populations
Cover crop germination was not uniform in early November. To more accurately capture cover crop establishment success, cover crop and weed populations were counted using the beaded string method, as opposed to randomly selecting locations to sample for biomass. On 4-Nov, populations were counted on five 10-foot lengths in each of the 24 plots.

Overall, cover crop populations were very low, covering between 10-13% of the field (Table 24). There were negligible or no differences in cover crop populations between the conventional and no-till systems, lower and higher corn seeding rate, and corn variety. Of the cover crop present, 76% was ryegrass, 24% radish, and 0% clover established. Percent cover of weeds averaged at 0% regardless of tillage system, seeding rate, or corn variety. What few weeds were present were predominantly barnyard grass.

Table 24. Corn and weed populations measured with the beaded string method.

Management

Cover Crop

Weeds

 

%

%

Conventional

13

0

No-Till

10

0

30,000 rate

12

0

35,000 rate

12

0

TMF2Q419

11

0

TMF2L395

13

0

The top performer for a category is highlighted in bold.

Table 25 below shows the average yields at the different plant populations for each of the other variables. We did observe the expected trend of increasing yield with increasing population for fixed ear, vertical-leaf architecture varieties. Similarly, for flex ear, horizontal-leaf architecture varieties, we saw slightly higher yields at lower populations but the trend was less clear than with the fixed ear varieties. We also saw some difference between long and short season varieties with the long season varieties outperforming the short season varieties by an average of 0.8 tons-1. Figure 7 shows the average yield across populations for fixed and flex ear varieties. At populations above 32,000 plants ac-1, the fixed ear varieties outperformed the flex ear varieties by approximately 2-3 tons ac-1. At lower populations there was little difference between the two ear types.

Table 25. Yields across treatments.

Population

Average Yield at 35% DM (tons ac-1)

Overall

Fixed ear

Flex ear

Long season

Short season

28,000

23.6

23.6

23.5

23.9

23.2

30,000

24.5

23.8

25.2

24.2

24.8

32,000

25.1

26.2

24.1

24.7

25.5

34,000

25.6

27.0

23.9

26.1

25.2

36,000

27.3

29.0

25.6

27.7

26.9

 

The other aspect of this project is whether these potential yield differences across populations influence cover crop establishment. One way we did this was to measure the amount of light available to the emerging cover crop in each of these scenarios. The percent of PAR light infiltrating through the crop canopy across the season is shown in Figure 8.

 

Effect of corn architecture and interseed timing- Rainville location

 

Table 26 below shows the average yields at the different interseeding timings for each of the other variables. Yields did not differ substantially across the interseeding timings for fixed or flex ear varieties (Figure 9). Similarly, both long season and short season varieties performed similarly across the interseeding timings. The other aspect of this project is whether these potential yield differences across populations influence cover crop establishment. One way we did this was to measure the amount of light available to the emerging cover crop in each of these scenarios. The percent of PAR light infiltrating through the crop canopy across the season is shown in Figure 10. The timings of the various growth stages that were interseeded at are pointed out on the figure. You can see that interseeding at V2 or V4 allowed emerging cover crop seed to have access to virtually 100% of the total available PAR whereas by V6 the corn canopy was beginning to obstruct the available light leaving about 85% for the cover crop to emerge and establish with.

Table 26. Yields across treatments.

Interseed Timing

Average Yield at 35% DM (tons ac-1)

Overall

Fixed ear

Flex ear

Long season

Short season

V2

21.2

21.6

20.7

20.9

21.4

V4

22.6

21.9

23.3

21.1

24.0

V6

21.1

20.4

21.8

21.1

21.2

Effect of corn architecture, seeding rate, and hybrid- Foster Farm

 

Corn Populations and Yield

Overall, yields seemed to be correlated to hybrid more than population at this location.  Late planting, heavy clay soil and wet weather combined for a low overall yield average of all plots of 14.5 tons acre-1  (adjusted to 35 percent dry matter values) (Table 27).

 

Overall plant populations were low compared to targeted planting populations.  This was likely due to a very wet spring and wetter than desired planting conditions.  One item of note in population was the hybrid TMF2L395 had higher population in the sampling observation at the lower seeding rate. This may be an anomaly of sampling.  There was no difference in yield by population in this hybrid.

 

 

Table 27. Plant populations and yields of corn hybrids and seeding rate

Hybrid

Seeding Rate

Plant Population @ V4±

Plant Population @ Harvestπ

Yield 35% DM

 

plants ac-1

plants ac-1

plants ac-1

tons ac-1

TMF2Q419

30,000

24,778

26,000

13.1

TMF2Q419

35,000

29,111

30,667

13.6

TMF2L395

30,000

24,667

33,000

15.6

TMF2L395

35,000

26,222

29,333

15.6

 

 

 

Average

14.5

           

   

Cover Crop Populations & Biomass
Cover crop germination was fairly uniform.  Anecdotal observations showed that where the previous year’s winter rye cover crop residue was heavier, there was better cover crop establishment and less weed competition.   All three species (annual ryegrass, red clover, and radish) were observed to have germinated well.  In addition, there was some additional volunteer red clover in the field.  Cover crop establishment was attempted to be quantified during the corn growing season by using Canopeo ‘fractional green canopy cover’ measurement.  However, the smart phone app and associated web-based platform was not functioning properly during this growing season so we were unable to utilize this technology.   To align with the other sites, we collected percent cover using the beaded string method (line transect method) on two dates – once at corn harvest (10/14/2019) and once three weeks after corn harvest (11/4/2019).  We also collected cover crop biomass by clipping four subsamples per plot, drying the clippings, and weighing the resulting dry plant material.

Interestingly, the hybrid that had the highest corn yield (and final corn population), TMF2L395, also had the highest cover crop biomass (Table 28).  This may be due to its more vertical leaf architecture.  Also of note, some treatments lost cover crop biomass between sampling events. 

Table 28. Cover crop percent cover and biomass by seeding rate and corn variety.

 

Cover Crop

 

% Cover

Biomass

 (pounds dry matter  ac-1 )

 

10/14/19

11/4/19

10/14/19

11/4/19

30,000 rate

39.0

38.3

514.9

613.6

35,000 rate

38.7

38.7

562.9

458.8

TMF2Q419

38.0

35.3

413.5

397.5

TMF2L395

39.7

41.7

664.2

674.9

TMF2Q419 @ 30,000 rate

39.3

32.0

384.1

378.8

TMF2Q419 @ 35,000 rate

36.7

38.7

442.8

416.2

TMF2L395 @ 30,000 rate

38.7

44.7

645.6

848.3

TMF2L395 @ 35,000 rate

40.7

38.7

682.9

501.5

Average

38.8

38.5

538.9

536.2

           

 

2020 Trial

Weather data was recorded with a Davis Instrument Vantage Pro2 weather station, equipped with a WeatherLink data logger at Borderview Research Farm in Alburgh, VT (Table 3). The season began with cooler than normal temperatures, but temperatures quickly increased and remained above normal for much of the season. Rainfall was below normal for much of the season with the region being designated as D0 or abnormally dry (Drought.gov) throughout the season. Much of the rain that fell throughout the season came in short duration storms. For example, in August there were only 6 rain events that accumulated at least 0.1”. Of these, 2 events totaled 1.53” and 2.98”, contributing 67% of the month’s entire accumulation. Furthermore, temperatures remained above normal for much of the mid-summer. In July, of 75% of the month saw temperatures climb above 80F with some days reaching above 90F. These temperatures contributed to above normal Growing Degree Days (GDDs) accumulations of 2485, 140 above the 30-year normal.

 

Table 3. 2020 weather data for Alburgh, VT.

 

May

Jun

Jul

Aug

Sep

Average temperature (°F)

56.1

66.9

74.8

68.8

59.2

Departure from normal

-0.44

1.08

4.17

0.01

-1.33

 

 

 

 

 

 

Precipitation (inches)

2.35

1.86

3.94

6.77

2.75

Departure from normal

-1.04

-1.77

-0.28

2.86

-0.91

 

 

 

 

 

 

Growing Degree Days (base 50°F)

298

516

751

584

336

Departure from normal

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.                                               

Trial 1 – Impact of Corn Population and Variety

Interactions

There was only one significant interaction between main effects (Table 4). A significant interaction between corn population and variety for cover crop dry matter yield indicates that the cover crop produced differing amounts of biomass when interseeded into the same corn variety planted at different populations. (Figure 1) displays these differences. For most varieties, a lower seeding rate resulted in higher cover crop biomass; however, 38N85, 9070AM, and SW4010 did not follow this trend. These three varieties had similar or higher cover crop biomass when corn populations were higher. This may be due to plant architecture.  The lack of other significant interactions indicates that corn varieties responded similarly in terms of yield and quality parameters when planted at different populations.

Table 4. Significance of main effects and main effect interactions.

 

Population

Variety

Population x Variety

Population

***

NS

NS

Corn yield

**

***

NS

Fall ground cover

***

*

NS

Cover crop dry matter

*

NS

NS

Cover crop yield

***

NS

*

Corn dry matter

NS

***

NS

Corn crude protein

NS

***

NS

Corn ADF

NS

*

NS

Corn NDF

NS

*

NS

Corn NFC

NS

NS

NS

Corn lignin

NS

**

NS

Corn ash

NS

*

NS

Corn fat

NS

***

NS

Corn starch

NS

**

NS

Corn digestible starch

NS

***

NS

Corn WSC

NS

*

NS

Corn uNDF30

NS

***

NS

Corn uNDF120

NS

***

NS

Corn uNDF240

NS

***

NS

Corn TDN

NS

**

NS

Corn NEL

NS

**

NS

Corn VFA

NS

***

NS

Milk yield (lbs ton-1)

NS

**

NS

Milk yield (lbs ac-1)

**

***

NS

* 0.1 < p > 0.05

** 0.05 < p > 0.01

*** p < 0.01

NS- Not statistically significant

Impact of Population

Corn population significantly impacted yield (Figure 2). Corn yields were significantly lower when populations of 28,000 and 34,000 plants ac-1 were used compared to 38,000. However, no additional yield benefit was observed from increasing from 28,000 to 34,000 plants ac-1. Population did not impact corn silage quality.

By two weeks after cover crop interseeding, the corn canopy had significantly closed reducing approximately 80% of the potential light infiltrating to the ground (Figure 3). Therefore, the newly planted cover crop had approximately 2-3 weeks from the time of seeding to germinate and establish prior to full canopy closure, in which very little light penetrated to the ground level for the remainder of the season. This demonstrates the challenge interseeding presents as any delay in seed germination or establishment (i.e. limited moisture, low vigor, etc.) significantly reduces the time available to the cover crop to properly establish increasing the chance of survival through the rest of the growing season.

Cover crop establishment also differed significantly by population (Table 5). Cover crops produced higher ground cover and biomass when interseeded into lower corn population stands. Ground cover significantly increased from 23.7% to 42% when populations were reduced below 34,000 plants ac-1. However, ground cover was not further impacted when populations increased from 34,000 to 38,000 plants ac-1. Similarly, cover crops produced over 300 lbs ac-1 more biomass when interseeded into corn at 28,000 plants ac-1 compared to corn at 34,000 plants ac-1. Cover crop biomass was not further impacted when populations were increased from 34,000 to 38,000 plants ac-1.

 

Table 5. Cover crop characteristics by population.

Population

Ground cover

Cover crop dry matter

Cover crop dry matter yield

plants ac-1

%

%

lbs ac-1

28,000

42.0a†

10.9b

877a

34,000

23.7b

12.3a

551b

38,000

25.6b

11.9ab

678b

LSD (p=0.10)‡

5.67

1.13

134

Trial Mean

30.4

11.7

702

†Treatments that share a letter performed statistically similarly to one another.

‡LSD; least significant difference at the p=0.10 level.

Impact of variety

Variety significantly impacted corn yield and quality parameters (Tables 6 and 7). Corn silage yields ranged from 20.7 to 27.9 tons ac-1 with the top performing variety, B94T73R, yielding similarly to only one other variety, B94T73SX. Crude protein (CP) averaged 8.23% with the top performing variety, 38N85, containing 8.80% protein. Protein levels were decent despite dry conditions that could limit nitrogen availability and negatively impact protein levels. Acid detergent fiber (ADF) and neutral detergent fiber (NDF) contents averaged 23.4% and 41.0% respectively. The lowest ADF and NDF contents were produced by variety B97T04SXE which had 21.1% ADF and 37.8% NDF. Four other varieties also performed statistically similarly to this variety in terms of both ADF and NDF content. Starch varied widely by variety ranging from 27.8% to 36.2% with the top performing variety, B97T04SXE, containing 3.6% more starch than the next highest variety. Water soluble carbohydrates (WSC) ranged from 5.99% to 7.81%. Total digestible nutrients (TDN) ranged from 61.9% to 64.6% with four other varieties performing similarly to the top performer. uNDF240 is the portion of the NDF fiber that remains undigested after 240 hours of exposure to rumen fluid. uNDF240 ranged from 10.2% to 12.8%. Net energy of lactation (Nel) ranged from 0.625 to 0.679 Mcal lb-1.

 

Table 6. Corn silage quality parameters by variety.

Variety

Yield at 35% dry matter

CP

ADF

NDF

Lignin

Ash

Fat

Starch

WSC

TDN

uNDF240

Nel

 

tons ac-1

% of DM

% of NDF

Mcal lb-1

B94T73R

27.9

8.01

24.8

42.7

3.13

4.55

2.99*

29.7

7.21*

63.2

12.2

0.647

B94T73SX

25.6*

8.06

26.0

44.5

3.28

4.83

2.66

27.8

6.76

61.9

12.8

0.625

B97T04SXE

24.2

8.19

21.1

37.8

2.73

4.11

3.25

36.2

5.99

64.6

10.2

0.679

CP3499VT2P

23.6

8.12

24.7

42.3

3.01*

4.75

2.87

30.4

6.83

62.8

11.7

0.641

P9608R

23.1

8.39

23.0*

40.1*

2.95*

4.61

3.20*

32.6*

6.59

63.8*

10.5*

0.664*

SW3768

23.2

8.47*

22.6*

39.8*

2.83*

4.87

3.10*

31.1

7.81

64.1*

11.0*

0.665*

SW4010

21.6

8.04

24.2

42.1

2.98*

4.85

2.66

30.5

6.93

62.8

12.0

0.641

38N85

20.7

8.80

21.7*

38.7*

2.79*

4.56

3.20*

32.3

6.93

64.2*

10.6*

0.671*

9070AM

23.3

7.94

22.9*

40.8*

2.82*

4.56

2.86

32.3

7.32*

63.7*

11.5

0.659*

LSD (p=0.10)

2.30

0.374

2.66

3.62

0.289

0.401

0.286

3.78

0.859

1.32

1.06

0.026

Trial Mean

23.7

8.23

23.4

41.0

2.95

4.63

2.98

31.4

6.93

63.4

11.4

0.655

* Varieties with an asterisk performed statistically similarly to the top performer in bold

 

Table 7. Predicted milk yield by variety.

Variety

Milk yield

 

lbs ton-1

lbs ac-1

B94T73R

3275

31808

B94T73SX

3175

28534

B97T04SXE

3405

28935

CP3499VT2P

3267

27015

P9608R

3359*

27125

SW3768

3369*

27366

SW4010

3238

24617

38N85

3402*

24599

9070AM

3298*

26843

LSD (p=0.10)

111

2756

Trial Mean

3310

27427

* Varieties with an asterisk performed statistically similar to the top performer in bold.

Post-harvest ground cover was also significantly impacted by corn variety, however, cover crop biomass was not (Table 8). Ground cover ranged from 20.2% in plots with variety CP3499VT2P to 38.4% in plots with variety SW3768. Interestingly, high corn yield was not clearly associated with lower ground cover. For example, the second highest yielding variety, B94T73SX, had a statistically similar level of ground cover as variety SW3768 which had the highest ground cover but yielded almost 2.5 tons ac-1 less than B94T73SX. This is important as it demonstrates that interseeding cover crops can be successful without compromising the yield of the corn crop (Figure 5).

 

Table 8. Cover crop characteristics by variety.

Variety

Ground cover

Cover crop dry matter yield

 

%

lbs ac-1

B94T73R

26.5bcd

805

B94T73SX

31.1abc

658

B97T04SXE

24.7cd

560

CP3499VT2P

20.2d

557

P9608R

36.0ab

717

SW3768

38.4a

900

SW4010

29.3abcd

652

38N85

32.7abc

728

9070AM

35.0ab

741

LSD (p=0.10)

9.82

NS

Trial Mean

30.4

702

Treatments that share a letter performed statistically similarly to one another.

The top performing treatment is indicated in bold.

Trial 2 – Impact of Cover Crop Interseed Timing

Deciding when to interseed a cover crop is challenging. On one hand you want to allow the cover crop time to establish before the corn blocks the light, but on the other hand, you don’t want the cover crop to compete with the establishing corn for resources. In addition, you want to make sure that corn herbicides do not impact the interseeded cover crop. Generally, corn can be interseeded anywhere from the V2 to V6 growth stage. After V6, most interseeding equipment is not tall enough, increasing the risk of damaging the corn crop.

Light available at the time of interseeding varied dramatically across the timing treatments (Figure 6) The arrows indicate the date the corn was interseeded corresponding to the V2, V4, and V6 growth stages. At the V2 and V4 growth stages, virtually none of the PAR was being obstructed by the corn canopy. However, by the time the corn reached the V6 stage, the canopy was already obstructing almost 50% of the light. Light infiltration continued to decline by approximately 10% each week until only 10% of the total light was infiltrating the canopy. This is the level that remained through the remainder of the season.

Despite the significant reduction in light available to the germinating cover crop in later interseedings, all timings supported similar cover crop establishment (Table 9). Post-harvest ground cover averaged 29.2% across the three timings and did not differ statistically. However, the majority of the ground cover was contributed by weeds, not interseeded cover crop species. This suggests that weed pressure throughout the season may have contributed to poor cover crop establishment and performance. As shown in Image 1, the dominant species that established and survived was the tillage radish. This is likely due to its large taproot that allowed it to access the limited moisture in the soil that the clover and annual ryegrass could not. Its wide leaves also allow it to compete for light resources better than the other species. Although the cover crops were assessed approximately 20 days after the corn was harvested, cover crop biomass was still too small to adequately sample. The corn in the trial yielded well averaging 23.7 tons ac-1 and did not vary across interseed timings. It is important to note that no damage was caused to the corn crop either from equipment at later interseedings or competition from the cover crop.

Table 9. Corn and cover crop characteristics by interseed timings, 2020.

Interseed timing

Yield at 35% dry matter

Dry matter

Ground cover

 

tons ac-1

%

% cover crop

% weeds

Total %

V2

22.9

36.8

6.55

28.3

34.8

V4

24.2

36.2

4.76

23.2

28.0

V6

23.9

37.2

5.95

18.8

24.7

LSD (p=0.10)

NS†

NS

NS

NS

NS

Trial Mean

23.7

36.7

5.75

23.4

29.2

†NS; Not statistically significant at the p=0.10 level.

Reports by Year:

2018 Interseeding Report

2019 Interseeding Report

2020 Interseeding Report

 

Research conclusions:

Interseeding cover crops into corn silage systems is challenging and may have higher success given changes to corn variety selection, populations, and the timing of interseeding. Determining the best combination of characteristics that support high yielding corn crops, and successful cover crops, requires multiple years of data to better understand how these variables interact under varying conditions. More data needs to be collected to better understand the interaction of these corn hybrid characteristics with crop management.

Participation Summary
7 Farmers participating in research

Education

Educational approach:

This project combines on-farm research and outreach/education methods to transfer information and knowledge to farmers.  In addition to gathering data at farm research locations, we will utilize these sites for educational opportunities.  Locations were chosen to be conducive to effective research, but also to be geographically spread out to maximize our outreach efforts. The ability to show producers our results is a major focus of our educational plan.  Seeing results first-hand in the field has a major impact on understanding and the rate of adoption.  In addition to 5 on-farm field days, we will utilize educational materials including the development of a “Guide to Interseeding Cover Crops” and a 6 session webinar series addressing practices that lead to successful establishment of interseeded cover crops. We will also share results at the No-Till & Cover Crop Symposium and other regional dairy and forage workshops in VT, ME, NH, NY.

In 2018, the project team hosted 3 field days in Vermont. Field days included general information on cover cropping including implementation strategies, benefits, and risks. In addition, information related to soil health was presented to attendees. The 3 fields (Alburgh, Franklin, and Addison) had 210 farmers and 102 other stakeholders in attendance. Flyers from the field days can be found below:

2018-Field-Day-Flyer

Summer Field Day – Franklin

The Cover Crop No-Till Conference held in winter of 2018 allowed the team to introduce the project to a broad group of stakeholders included over 100 farmers and 125 TSPs. In addition, technical cover crop information from both research and practitioners was presented to the audience of 225.

Project outreach also occurred through web resources including an article in a local newsletter (https://www.uvm.edu/sites/default/files/Agriculture/cv-crops-newsletter-2018-fall.pdf) and bulletin (Interseeding Cover Crops into Corn Silage).

In 2019, there were 3 field days in VT and 3 held in ME.

In Vermont, there were 3 meetings held in Alburgh (25-Jul-19;), Franklin (14-Aug-19), and Middlebury (14-May-19) VT. There were a total of 385 participants that attended the events.Topics at the events included cover crop species evaluation trials, cover cropping management, and interseeding equipment, interseeding techniques, corn production for cover crops, and roller-crimping technology. 

In Maine, there were 3 meetings held in Orono (14-Mar-19;), Clinton (21-Aug-19), and Corinna (30-May-19) ME. There were a total of 99 participants that attended the events.Topics at the events included managing herbicides in interseed systems, cover cropping management, and interseeding equipment. 

The Cover Crop No-Till Conference held in winter of 2019 allowed the team to report on the first year of research trials as well as a farmer to farmer session on innovative cover crop techniques. There were 63 farmers and 58 TSPs. In addition, technical cover crop and no-till information from both research and practitioners was presented to the audience of 121.

The Cover Crop No-Till Conference held in winter of 2019 allowed the team to introduce the project to a broad group of stakeholders included over 63 farmers and 57 TSPs. In addition, technical cover crop information from both research and practitioners was presented to the audience of 120.

In 2020, there were limited in-person outreach events due to the pandemic. However the project team was still able to hold outreach events and provide cover crop information and resources to the farming community

In March and April of 2020, a webinar series as held focused on cover crops and other conservation practices. Attendees participating from throughout the region. Presentations were recorded and archived on YouTube with links below. 

Dig into Your Day with Cover Crops & Conversation webinar series  

Precision Sustainable Agriculture with Steve Mirsky (23 Mar 2020) 123 views https://www.youtube.com/watch?v=kMad0D7WjqQ 

Cover Crops in the Corn/Soybean Rotation with Peter Tomlinson (26 Mar 2020) 99 views https://www.youtube.com/watch?v=K-QHtvmzJaQ 

No-till and Cover Crops in Organic Systems with Joel Gruver (2 Apr 2020) 659 views https://www.youtube.com/watch?v=wQYufKlsm_M 

No-till and Cover Crops in Vegetable Systems with Natalie Lounsbury (6 Apr 2020) 85 views https://www.youtube.com/watch?v=sWDxJhFlGE4 

Stewarding the Birthplace of No-till with John and Alexander Young (Apr 2020) 47 views https://www.youtube.com/watch?v=wMjsg03YJUA 

Cover Crop and Soybean Research with Heather Darby (13 Apr 2020) 76 views https://www.youtube.com/watch?v=oj2GA4g8Ze8 

Virtual Friday Field Days were held throughout the growing season highlighting various research projects at Borderview Research Farm. Cover Crops, interseeding, and various experiments associated with these practices were highlighted.

Virtual Field Day Fridays 2020   

Welcome to our Virtual Field Day Fridays (24 Jul 2020) 76 views https://www.youtube.com/watch?v=wsTHZyOrYLY&feature=youtu.be 

Brassica Cover Crops on Vegetable Farms in the Northeast (24 Jul 2020) 59 views https://www.youtube.com/watch?v=RzAe3gFGJpU&feature=youtu.be 

Solar Corridors Cropping Systems Experiment (5 Aug 2020) 73 views https://www.youtube.com/watch?v=nM-BO-rNYVk&feature=youtu.be 

Interseeding and Equipment at Borderview Research Farm (5 Aug 2020) 86 views https://www.youtube.com/watch?v=EQqtApqE45A&feature=youtu.be 

Corn Silage Trials: Flex vs. Fixed, Populations, and Impacts of Drought (19 Aug 2020) 69 views https://www.youtube.com/watch?v=pMDzDqiROGY&feature=youtu.be 

A Day at Borderview Research Farm (10 Sep 2020) 47 views https://www.youtube.com/watch?v=vsAAnqYkLCc&feature=youtu.be 

Soil Dynamics of Cover Crops: Rye, Vetch, and a Mix (17 Sep 2020) 79 views https://www.youtube.com/watch?v=vX_WWwd1f3I&feature=youtu.be 

Winter Terminated Cover Crops UVM (17 Sep 2020) 69 views https://www.youtube.com/watch?v=TFXvYiOsI5Q&feature=youtu.be 

September 9th  Field day at Misty Meadows farm with 48 participants (state limit of 50 people for outdoor events). Discussed corn varieties as well as interseeding, herbicide issues and 60 inch row corn.

Milestones

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

1. 1550 dairy farmers in the 5 New England states and northeastern NY will first learn of the project and performance target at the 2018 No-Till/Cover Crop Conference (Burlington, VT; 200 attendees from region). In addition farmers will hear of the project through our outreach networks including social media and newsletters (distribution 1350). March 2018

Proposed number of farmer beneficiaries who will participate:
1550
Actual number of farmer beneficiaries who participated:
1590
Actual number of agriculture service provider beneficiaries who participated:
65
Proposed Completion Date:
March 31, 2018
Status:
Completed
Date Completed:
June 15, 2018
Accomplishments:

The project and performance target was announced at the 2018 No-Till & Cover Crop Symposium held in Burlington, VT on March 1st, 2018. There were 225 attendees from around the region (NY, VT, MA, NH, and Quebec).  Project announcement continued through UVM Extension social media, list serves, and newsletters where we were able to distribute the announcement to 1365 additional stakeholders. A press release was developed and sent to 10 local media outlets for distribution.

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

2. Two hundred fifty dairy farmers attend cover crop workshops and webinars and learn about how modifying corn production practices can improve cover crop establishment and benefits. August 2018 & 2019

Proposed number of farmer beneficiaries who will participate:
250
Actual number of farmer beneficiaries who participated:
495
Actual number of agriculture service provider beneficiaries who participated:
334
Proposed Completion Date:
August 31, 2019
Status:
In Progress
Accomplishments:

In 2018, the project team hosted 3 field days in Vermont. Field days included general information on cover cropping including implementation strategies, benefits, and risks. In addition, information related to soil health was presented to attendees. Flyers from the 2 of field days can be found below:

2018-Field-Day-Flyer

Summer Field Day – Franklin

In 2019, the project team hosted 3 field days in Vermont and 3 in Maine. Field days included general information on cover cropping including implementation strategies, benefits, and risks. In addition, information related to soil health was presented to attendees. Interseeding and other cover cropping equipment was available for demonstration and to view. At one field day farmers were able to view a variety of cover crops growing and various soil health benefits from the species. Farmers were shown how to operate the equipment at some of the field days. Experiments were also highlighted. Flyers from two of the field days are attached.

Annual Crop and Soil Field Day – 2019

Annual Summer Field Day – 2019

 

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

3. 4 farmer collaborators will assist with the development and implementation of research to identify best corn practices to establish interseeded cover crops. May 2018; 2019

Proposed number of farmer beneficiaries who will participate:
4
Actual number of farmer beneficiaries who participated:
4
Proposed Completion Date:
May 31, 2019
Status:
In Progress
Accomplishments:

1n 2018, on-farm research was established at 2 sites in VT and 2 sites in ME. The research trials evaluated the impact of corn variety and corn seeding rate on the establishment of cover crops that have been interseeded. Corn yields were recorded as well as cover crop establishment.

1n 2019, on-farm research was established at 2 sites in VT and 2 sites in ME. The research trials evaluated the impact of corn variety and corn seeding rate on the establishment of cover crops that have been interseeded. Corn yields were recorded as well as cover crop establishment. Unfortunately the ME sites had significant weather challenges and complete data was not collected. Vermont sites were able to repeat the trial at the on-farm locations.

Although the trial field work is completed the data is still being analyzed and compiled.

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

4. 100 farmers attend field days and webinars demonstrating the combination of corn production practices with cover crop interseeding and learn about practical management tools for their operation. August 2020

Proposed number of farmer beneficiaries who will participate:
100
Proposed Completion Date:
August 31, 2020
Status:
In Progress
Accomplishments:

Final corn interseeding intensive will be held at the 2020 UVM Annual Field Day.

Milestone #5 (click to expand/collapse)
What beneficiaries do and learn:

5. 50 farmers interested in “trying” interseeding and corn management will receive a project factsheet and enrollment form that outlines expectations. June 2018; 2019

Proposed number of farmer beneficiaries who will participate:
50
Actual number of farmer beneficiaries who participated:
29
Proposed Completion Date:
June 30, 2019
Status:
In Progress
Accomplishments:

A flyer was developed to recruit farmers to “try” the practice of interseeding (. The flyer was distributed through emails, newsletters, blogs, and facebook (distribution 1365). Interested farmers contacted the UVM Extension office to participate. Farmers were provided one-on-one technical assistance for interseeding. UVM Extension also completed the interseeding for many farms.

In 2019, interseeding on-farms continued. There were 9 new farms that worked with UVM to “try” interseeding into 445 acres of corn silage. This work will be continued in 2020.

Milestone #6 (click to expand/collapse)
What beneficiaries do and learn:

6. The farmers that agree to participate will receive basic recordkeeping notebooks, one-on-one technical assistance with interseeding and implementation of practices and documentation of changes in corn silage cropping system. December 2020

Proposed number of farmer beneficiaries who will participate:
50
Actual number of farmer beneficiaries who participated:
29
Proposed Completion Date:
December 31, 2020
Status:
In Progress

Milestone Activities and Participation Summary

75 Consultations
1 Curricula, factsheets or educational tools
4 On-farm demonstrations
1 Published press articles, newsletters
10 Webinars / talks / presentations
9 Workshop field days

Participation Summary

552 Farmers
466 Number of agricultural educator or service providers reached through education and outreach activities

Learning Outcomes

22 Farmers reported changes in knowledge, attitudes, skills and/or awareness as a result of their participation
12 Service providers reported changes in knowledge, attitudes, skills and/or awareness as a result of project outreach
12 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:

Farmers were provided a post event survey at the no-till & cover crop conference.

The most common response was to try to increase cover crop acreage, increase cover crop productivity, and increase cover crop species diversity were all indicated by attendees as areas where they planned to implement knowledge and make change to their operations.

Performance Target Outcomes

Target #1

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.