ohio state university extension -...

Homegrown NitrogenJames J. Hoorman [email protected] Sundermeier [email protected]. K. Rafiq Islam [email protected]

[email protected]

OHIO STATE UNIVERSITY EXTENSION

mailto:[email protected]:[email protected]:[email protected]

Type of Cover Crops

Legumes: Make Nitrogen, low C:N ratio, tap root,cowpeas, Austrian winter pea, hairy vetch,red & sweet clover, Sunn hemp, lupins, soybeans

Grasses: Accumulate nutrients (fine roots), C:N ratio depends on killing date: oats, wheat, cereal rye,annual ryegrass, barley, Sudan-sorghum, millets

Brassicas: Good for surface compaction and weed control: Daikon radish, turnips, kale, rape


Legumes & Clovers

1) Make N with the help of Bacteria2) Provide N to grasses3) Longer deeper tap roots, help with

deep vertical compaction.4) Recycle P and K5) Acidify the soil, less root mass


Red clover

Crimson clover


White Clover

Yellow Clover


http://images.google.com/imgres?imgurl=http://bolincreek.org/images/WhiteClover.jpg&imgrefurl=http://bolincreek.org/wildflowersarchive.shtml&usg=__lyDNmFzclKl-IVvvGPFDTVvjcQ0=&h=400&w=400&sz=31&hl=en&start=5&tbnid=qEW6c2u72qKiLM:&tbnh=124&tbnw=124&prev=/images%3Fq%3Dwhite%2Bclover%26gbv%3D2%26hl%3Den%26safe%3Dstrict%26client%3Ddell-usuk-rel%26channel%3Dus%26ad%3Dw5http://images.google.com/imgres?imgurl=http://bolincreek.org/images/WhiteClover.jpg&imgrefurl=http://bolincreek.org/wildflowersarchive.shtml&usg=__lyDNmFzclKl-IVvvGPFDTVvjcQ0=&h=400&w=400&sz=31&hl=en&start=5&tbnid=qEW6c2u72qKiLM:&tbnh=124&tbnw=124&prev=/images%3Fq%3Dwhite%2Bclover%26gbv%3D2%26hl%3Den%26safe%3Dstrict%26client%3Ddell-usuk-rel%26channel%3Dus%26ad%3Dw5http://images.google.com/imgres?imgurl=http://image60.webshots.com/60/1/24/89/486312489LrHvVL_fs.jpg&imgrefurl=http://home-and-garden.webshots.com/photo/1486312489072653674LrHvVL&usg=__JnPVtdzkt87saBxEz734Ru2JiWU=&h=1200&w=1600&sz=160&hl=en&start=9&tbnid=CmrfHwXKgbpQFM:&tbnh=113&tbnw=150&prev=/images%3Fq%3DYellow%2Bclover%26gbv%3D2%26hl%3Den%26safe%3Dstrict%26client%3Ddell-usuk-rel%26channel%3Dus%26ad%3Dw5http://images.google.com/imgres?imgurl=http://image60.webshots.com/60/1/24/89/486312489LrHvVL_fs.jpg&imgrefurl=http://home-and-garden.webshots.com/photo/1486312489072653674LrHvVL&usg=__JnPVtdzkt87saBxEz734Ru2JiWU=&h=1200&w=1600&sz=160&hl=en&start=9&tbnid=CmrfHwXKgbpQFM:&tbnh=113&tbnw=150&prev=/images%3Fq%3DYellow%2Bclover%26gbv%3D2%26hl%3Den%26safe%3Dstrict%26client%3Ddell-usuk-rel%26channel%3Dus%26ad%3Dw5

Legume hemp (Crotalaria)


Sunn Hemp

http://upload.wikimedia.org/wikipedia/commons/2/26/Crotalaria_retusa_MS_1793.JPGhttp://upload.wikimedia.org/wikipedia/commons/2/26/Crotalaria_retusa_MS_1793.JPG

Sunn Hemp

•


Cowpea Black-eyed pea


Cover crops biomass production

Cover cropsCpea CClov Gbean Hvetch RClov Wpea

Dry

bio

mas

(lbs

acre

-1)

0

2000

4000

6000

8000

10000


Biomass N content of cover crops


N c

onte

nt (%

)

0

1

2

3

4

5


Biomass N contribution


N c

ontr

ibut

ion

(lbs

acre

-1)

0

50

100

150

200

250

300

350

Total NN contribution



C:N

ratio

0

5

10

15

20

25

30

Cover Crops C:N ratioOHIO STATE UNIVERSITY EXTENSION

Crimson CloverOHIO STATE UNIVERSITY EXTENSION

Crimson CloverDisadvantages

• VNS will possibly winterkill

Advantages• Can produce up to 140

units of N/acre within 90 days following wheat

• Earthworm “Heaven”• Easy to kill• Excellent new (early

and more winterhardy) varieties are available: Daisy


Crimson Clover -2Advantages

• Works very well as a companion to Radishes, Annual Ryegrass, etc...

• Deep and fibrous root system (21” deep)


Crimson Clover roots…found 34” deep spring 2011 (in sandy loam soil)


Austrian Winter Peas

Advantages• Produces 60-

150#/acre N • Generally Winterkills• Easy to kill with

herbicides

Disadvantages• Best to be

incorporated• Generally Winterkills• Needs at least 5-6

weeks growth for best results

• Only one grazing/harvest can be expected


Austrian winter pea (winter pea)


Ohio NT farmers association president David Brandt standing in his NT winter pea field


Wheat/Cow peasRye

Soybean Wheat

NT Crop Rotation with Minimum N InputCorn


Shoot

89%(8948 lbs ac-1)

11%

(960 lbs ac-1

)

Winter pea dry biomass partitionRoot

130-150 lbs N contribution per acre


Cowpea

Corn, no nitrogen added


9%(708 lbs ac-1)

91%(6928 lbs ac-1)

Cowpea dry biomass partitionRoots

Shoot

138-152 lbs N contribution per acre


No-Till corn in winter-killedcowpea without N fertilization

Conv. tilled corn with Nfertilization


NT corn in winter killedcow pea residues

NT corn with Nfertilization


Plowed fieldNo-till w/cover crops

July 2008


Corn no-tilled into Austrian Winter PeaPhotos: July 6, 2009

Bill Richards’ Farm, Circleville, Ohio


Remains of Austrian Winter Pea cover crop, July 6


Medium Red Clover

Disadvantages• May get too tall in

wheat and affect harvest/Harder to kill.

Advantages• Produces 75-100# N• Good root system-soil

builder• Easy to frost seed

into wheat• Often least cost cover

crop• Excellent for forage


2010 NW Ag Research Station, Wood County, OH

Red Clover: No-Till________________________________________

Treatment Corn Yield

No-Till 130 A

No-Till & Clover 139 B________________________________________________

LSDp=0.10 5.8


2010 NW Ag Research StationRed Clover - Tillage

Treatment Corn YieldNoTill 129.8 ANoTill & Clover 138.6 BConserv. Tillage 139.3 B CConserv. Tillage & Clover 144.8 C

LSD (.10) 5.8


When/How much N Fertilizer needed if using Legume before Corn?

When do you need fertilizer? Early spring and summer when temperatures are cool.

How much N fertilizer? Depends on PSNT.Suggest 40-60# of N fertilizer as starter.Watch salt content.

When is Legume N released? Depends on moisture and temperature. Most is released in 30 to 90 days or later in growing season.


Planting Legume Cover CropsCrop rotationTime of plantingInoculationBroadcast vs. Drilling


Broadcasting/drilling Example: Austrian winter peas


1) Legume Cover Crops may be a significant source of Soil Nitrogen.

2) Biomass N equals Biomass Production * N content

3) Crimson Clover after Wheat Up to 140# NA

4) Cowpeas after Winter Wheat138-152 #N/Acre.

5) Austrain Winter peas after Winter Wheat130-150 #N/Acre. Canadian Field Pea 50-100#N/A

6) Red Clover after Wheat 75-90 #N

Summary of Legumes


Slide Number 1Slide Number 2Slide Number 3Slide Number 4Slide Number 5Slide Number 6Sunn HempSlide Number 8Slide Number 9Slide Number 10Slide Number 11Slide Number 12Crimson CloverCrimson CloverSlide Number 15Crimson Clover roots…found 34” deep spring 2011 (in sandy loam soil)Austrian Winter PeasSlide Number 18Slide Number 19Slide Number 20Slide Number 21Slide Number 22Slide Number 23Slide Number 24Slide Number 25Slide Number 26Slide Number 27Slide Number 28Medium Red CloverSlide Number 30Slide Number 312010 NW Ag Research Station�Red Clover - Tillage When/How much N Fertilizer needed if using Legume before Corn?Slide Number 34Slide Number 35Slide Number 36

ohio state university extension -...

Documents