The Penn State Interseeder Project for In-Crop Establishment of Cover Crops

W. Curran, G. Roth, C. Dillon, C. Houser, R. Hoover, J. Wallace, M. Dempsey, Penn State University; S. Mirsky, USDA-ARS; and M. Ryan, Cornell University

Special thanks to Cover Crop Solutions, Kings AgriSeeds, and Seedway for their support.

•Dairy – corn and hay dominate •Smaller diverse livestock, grain and/or vegetable farms common •Reduced and no-till the norm

Regional perspective

• Important watershed • Diverse agricultural systems

• High density of animal agriculture

• No-till enthusiasm

• Lots of interest in cover crops

• Incentive programs

• Interest in sustainable and organic agriculture

The Mid-Atlantic Region

Hairy Vetch Cereal Rye Oats

Red Clover Winter Wheat Forage Radish

Cover crops – can be a valuable part of the cropping system

Benefits from cover crops

Magdoff, F.R., and H.M. van Es. 2009. Building Soils for Better Crops: Sustainable Soil Management. Handbook Series Book 10. Sustainable Agric. Research and Education, Waldorf, MD.

Cover Cropping Success

• Cover crops are widely adopted following corn for silage and after small grains in our region

• Benefits include soil improvement, forage production and reducing runoff and erosion

Cover Crop Incentives

Several Aggressive Cover Crop Seed Companies • Cover Crop Solutions • Kings AgriSeed • Seedway • Others

http://www.ctic.org/media/CoverCrops/CTIC_04_Cover_Crops_report.pdf

Conservation Technology Information Center - CTIC

Increasing cover crop use

http://www.ctic.org/media/CoverCrops/CTIC_04_Cover_Crops_report.pdf

http://www.ctic.org/media/CoverCrops/CTIC_04_Cover_Crops_report.pdf

N = 1,415

Cover Cropping Barriers

• Following grain harvest or even silage in some areas there is limited opportunity for establishment

• Cost of establishment and benefits of late planted cover crops are concerns

Previous attempts to expand cover cropping have had limited success

• Aerial applications inconsistent

• Late drilling has little benefit in fall and later development in spring

Aerial seeding red clover in soybean

Charlie Martin’s high-boy interseeder

Alternatives to post-harvest seeding

Early season interseeding

• Seed cover crops at V6 corn

• After critical weed-free period for corn

• Some experience in Europe, Canada and Pacific NW

• Previous tests indicate that when timed right, minimal or no impact on yields

Today’s Objective

• Provide update Penn State Interseeder design

• Share results of on-going research

Penn State Interseeder Project

• First tested in 2010

• No-till machine that is multifunctional

• Can also apply sidedress N and herbicide

• First design had in-row coulter tillage

• Broadcast seed distribution in inter-row zone

• Packing wheels to cover seed

Latest Version Design Components

• Drill units between rows

• Liquid N stream applied adjacent to corn row

• Herbicide applied under corn canopy

• Assist wheels to carry weight

• Ground drive

• Loading platform

• Conversion to complete Drill Unit

• Hitch for towing

• More accurate seed depth

• Better seed coverage

• Better furrow closure

• Less seed in surface herbicide treated zone

• Potential for moisture accumulation in furrows

Row Units

Commercialized by Interseeder Technologies, LLC - http://interseeder-tech.com/ • Currently

marketing 4 and 6 row machines with various configurations

Interseeding in V6 corn Crimson clover about 4 and 8 weeks after interseeding

Red clover in the fall prior to corn harvest.

Annual ryegrass cover after corn silage harvest in the fall.

NRCS Conservation Innovation Grant (CIG) Project – PA, MD, and NY (2012-2015)

• Evaluate new design under different on-farm conditions

• Compare different cover crop species and mixtures

• Document impact on host and subsequent crops

Curran, WS, GW Roth, R. Hoover, J. Wallace, MR Ryan, and SB Mirsky. 2012. Maximizing conservation in the Chesapeake Bay Watershed with an innovative new 3-way interseeder for early establishment of cover crops in no-till corn and soybean. NRCS CIG.

CIG Project - Five Experiments

• Experiment 1 - On-farm protocol. This trial is testing four or five cover crop treatments across many locations in three states (MD, NY, and PA). This trial is looking at both cover crop and corn performance the year of establishment and in rotation

• Experiments 2 and 3 - Species and variety experiments. The cover crop species and annual ryegrass variety experiments were conducted at single locations in PA, MD, and NY in 2013 and 2014.

• Experiment 4 - Interseeding in soybean. Soybeans were planted in May or June and interseeded 4 to 6 weeks after planting. This experiment was conducted at 3 locations in 2013 and repeated in 2014 (not discussed today).

• Experiment 5 - Herbicide safety. The safety of herbicides was examined in Pennsylvania in 2013 and in three states in 2014.

2013-2014 Experience in the Field

General Methods

• Most trials no-till (except some in NY)

• Trials established in soybean stubble (some in corn)

• Most plots either 4 or 8 rows (76 cm) wide ranging from 20 to 300 m in length

• All trials had 3 or 4 reps

• Corn planted during May and interseeded about 6 weeks later (V5-V7)

• No residual herbicides used in most of these trials (Burndown plus Post) using Roundup Ready corn

• Cover crop biomass harvested in late fall and spring and cash crop yield collected

• On-farm trials also investigated second year performance

On-Farm research trials (about 12 locations each in 2013 and 2014) Treatment Species Rate (kg/ha)

1 Untreated No cover crop 0

2 Grass Annual ryegrass 22

3 Legumes mix Med. red clover, crimson

clover, hairy vetch

11+22+17

4 Legumes + grass Annual ryegrass, med.

red clover, crimson

clover, hairy vetch

11+6+11+8

5 Grass + radish

(2014 only)

Annual ryegrass, radish 11+6

2013 fall cover crop biomass averaged over 5 locations (3 PA and 2 NY)

Standard error of the mean (SE) bars presented Significant differences due to cover crop

0 100 200 300 400

Radish

Grass-legumemix

Legume mix

AnnualRyegrass2

AnnualRyegrass1

Kg/ha

2013 fall cover crop biomass at 5 locations (3 PA and 2 NY)

Standard error of the mean (SE) bars presented Significant differences in sites and cover crops

0 200 400 600 800

Radish

Grass-legume mix

Legume mix

Annual Ryegrass2

Annual Ryegrass1

Radish

Grass-legume mix

Legume mix

Annual Ryegrass2

Annual Ryegrass1

Grass-legume mix

Legume mix

Annual Ryegrass

Grass-legume mix

Legume mix

Annual Ryegrass

Grass-legume mix

Legume mix

Annual RyegrassR

DM

GR

SLV

FR

Kg/ha

Landis- ville (PA)

Franklin (PA)

Rock Sprgs. (PA)

Aurora (NY)

Adams Ctr. (NY)

Fall and spring cover crop biomass in PA (2013)

Standard error of the mean (SE) bars presented Significant differences in sites and cover crops

Spring cover crop biomass at Rock Springs in 2014 was unusually low due to the severe winter. Crimson clover did not survive the winter and spring growth was delayed with other cover crops.

0 500 1000 1500 2000 2500 3000

Annual Ryegrass1

Grass-legume mix

Legume mix

Annual Ryegrass1

Grass-legume mix

Legume mix

Annual Ryegrass1

Grass-legume mix

Legume mix

Fran

klin

Lnd

ville

Ro

ck S

pr.

Kg/ha

Fall biomass

Spring biomass

Union County October 2014 Erie County November 2013

Chambersburg 2013 Interseeding: Spring 2014

On-farm trial in Central NY (October 30, 2013)

Vermont Fall 2013

Lancaster 2013: Summer

Lancaster 2013: Fall

What about corn yield?

2013 corn grain yield averaged over 5 locations (3 PA and 2 NY)

Standard error of the mean (SE) bars presented P = 0.36 (no significant difference due to cover crop)

160 = 10,000 kg/ha

Corn grain yield averaged over 5 locations (3 PA and 2 NY in 2013)

50 70 90 110 130 150 170 190 210 230

Radish

Grass-legume mix

Legume mix

Annual Ryegrass2

Annual Ryegrass1

Untreated control

Radish

Grass-legume mix

Legume mix

Annual Ryegrass2

Annual Ryegrass1

Untreated control

Grass-legume mix

Legume mix

Annual Ryegrass

Untreated control

Grass-legume mix

Legume mix

Annual Ryegrass

Untreated control

Grass-legume mix

Legume mix

Annual Ryegrass

Untreated controlR

DM

GR

SLV

FR

Bu/acre

P=0.03

P=0.89

P=0.05

P=0.80

P=0.43

Landis- ville PA)

Franklin (PA)

Rock Sprgs. (PA)

Aurora (NY)

Adams Ctr (NY)

Standard error of the mean (SE) bars presented

10,000 kg/ha

2014 PA Corn Grain Yields in On-Farm Study (year of interseeding)

(no significant difference due to cover crop)

Experiments 2 and 3 - Cover crop species (left) and annual ryegrass varieties (right). Cover crop seeds provided by multiple sources.

Cover Crop Species Kg/ha Annual Ryegrass Varieties

Kg/ha

1. Untreated 0 Untreated 0

2. Med red clover 11 DH3 22

3. Crimson clover 11 Bounty 22

4. Yellow sweet clover 11 SBA 22 22

5. Hairy vetch 22 Bruiser 22

6. Ladino clover 11 KB Supreme 22

7. Kentucky bluegrass 22 Rootmax 22

8. Perennial ryegrass 22 Winterhawk 22

9. Orchardgrass 22 King 22

10. Tall fescue 22 MO1 22

11. Annual ryegrass 22 Green Spirit 22

Species Study, Rock Springs - Mid October 2013

Annual ryegrass

Hairy vetch Red clover

Orchardgrass

Ladino clover

Kentucky bluegrass

Fall vs. spring cover crop biomass in the species study conducted at Rock Springs in Central PA in 2013

0 100 200 300 400 500

Annual ryegrass

Kentucky bluegrass

Orchardgrass

Hairy vetch

Yellow sweet clover

Ladino clover

Med red clover

Crimson clover

Kg/ha

Fall biomass

Spring biomass

Standard error of the mean (SE) bars presented Significant differences due to cover crop

Fall vs. spring cover crop biomass in the ryegrass variety study conducted at Rock Springs in Central PA in 2013

0 50 100 150 200 250 300 350

Winterhawk

SBA 22

Rootmax

MO1

King

KB Royal

Green Spirit

DH3

Bruiser

Bounty

Kg/ha

Fall biomass

Spring biomass

Standard error of the mean (SE) bars presented Significant differences due to variety

Herbicide Research

• Residual herbicides can be problematic for interseeded cover crops and requires planning ahead

• Look for short residual herbicides that don’t control both broadleaves and grasses all summer long (look for shorter half-life products)

• Our research is investigating successful options

• Nonresidual programs based on glyphosate or glufosinate (Liberty) are the safest approach until we have more experience

2013 & 2014 field trials at PSU-RELARC: silt-loam soils, pH = 6.5, %OM = 2.9

Whole-Plots (24 x 3 m): 13 residual herbicide treatments

Split-Plot (6 X 3 m): 4 cover crops interseeded in 8 corn rows (annual ryegrass, medium red clover, crimson clover, hairy vetch)

Management: No-till planted GR corn on 76 cm row spacing w/ burndown + 2-pass herbicide system (PRE + 30 DAP glyphosate treatment)

Interseeding: 35 DAP

Screening of residual herbicides for interseeding in corn

production systems

Herbicide Treatments tested in 2013/2014

Product Active Ingredient Prod/Acre MOA Half-Life

Grass Herbicides --- 1X --- (WSSA) (WSSA-HH)

Prowl H2O 3.8 CS pendimethalin 1.42 l 3 44

Dual II Magnum 7.64 EC s-metolachlor 790 l 15 15 – 50

Outlook 6 EC dimethenamid-P 0.473 l 15 20

Harness 7 EC acetochlor 0.946 l 15 10 – 20

Zidua 85 WG pyroxasulfone 71 g 15 16 – 26

Broadleaf Herbicides

Resolve 25 WG rimsulfuron 28 g 2 2 – 7

Atrazine 4 L atrazine 1.42 l 5 60

Metribuzin 75 WG metribuzin 113 g 5 30 - 60

Balance Flexx 2 SC isoxaflutole 157 ml 27 50 – 120

Callisto 4 SC mesotrione 160 ml 27 20-40

Impact 2.8 SC (*POST) topramezone 22 ml 27 14

Sharpen 2.85 SC saflufenacil 89 ml 14 7 - 35

PSU Research in Progress - Effect of herbicides on inter-seeded cover crops at Rock Springs in 2013 and 2014

(Corn planted early to mid May and inter-seeded mid to late June - plots evaluated late July)

(0 = no effect; 100 = complete loss – numbers in bold had most injury)

PSU Research in Progress - Effect of herbicides on inter-seeded cover crops at Rock Springs in 2013 and 2014

(Corn planted early to mid May and inter-seeded mid to late June - plots evaluated late July)

(0 = no effect; 100 = complete loss – numbers in bold had most injury)

Summary For Corn Herbicides Preliminary Recommendations for the Northeast

Grass Herbicides Active Ingredient

Injury Possible

Dual II Magnum 7.64 EC s-metolachlor*

Zidua 85 WG pyroxasulfone*

Potentially Safe Products

Prowl H2O 3.8 CS pendimethalin

Outlook 6 EC dimethenamid-P*

Harness 7 EC acetochlor*

Broadleaf Products Active Ingredient

Injury Possible

Callisto 4 SC mesotrione*

Impact 2.8 SC topramezone*

Balance Flexx 2 SC isoxaflutole*

Potentially Safe Products

Resolve 25 WG rimsulfuron

Atrazine 4 L atrazine (<1.12 kg)*

Sharpen 2.85 SC saflufenacil*

*Premixed products also contain many of these active ingredients

Short Residual Herbicide Use

Conclusions • Interseeding cover crops at V5 to V7

corn mostly successful in 2013 and 2014

• Residual herbicide programs must be adjusted to ensure cover crop success

• Annual ryegrass was the most successful grass cover crop with legume establishment being more variable

• Real benefits for holding N for next year’s crop

• Corn yield was mostly unaffected by interseeding during the year of establishment

• The effect of interseeded cover crops on 2nd year corn is still being assessed

Final Thoughts:

• Fairly high level of successful establishment • About 70% in 2013 and 90% in 2014 in over 70 trials

• Issues: • Geographic limitations - better in the North? (prefers

cooler and heavier soils)

• Identifying suitable species and varieties – annual ryegrass and medium red clover consistently two of the best

• Soil residual herbicides can be problematic – but often necessary to manage HR weeds

• Timely cover crop control the subsequent year

Thank you for your attention! Questions/Discussion?

Photo: Patrick Mansell, Penn State

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