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GrassHay and Pasture Nutrient Management

DanielH. Smith, CCASouthwest Regional Specialist

Nutrient and Pest Management ProgramUniversity of Wisconsin-Madison CALS and Division of Extension

@agronomybadger

Disclaimer: Any use of trade names is for descriptive purposes and does not represent an endorsement by the author.

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Soil Testing

• Estimate the nutrients needed for economically profitable forage production.

• 10 cores per 5 acres minimum standard= 1 composite sample.

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Soil pH Management

Recommended Target Soil pH

• Pasture pH= 6.0

• Pasture >30% legumes pH= 6.3

• Grass Hay pH= 6.0

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Nitrogen

Laboski C.A., Shelley, K.B. 2013. “Soil Fertility Guidelines for Pastures in Wisconsin” University of Wisconsin-Madison. Extension Publication A4034.

Similar levels recommended for nitrogen applications to grass hay fields.

Economics!

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Nitrogen Management inEstablished Pastures

• Pasture Species• >30% legume mixture, 30-50 lbs

N/ac/ yr transfered to grasses, nocommercial N necessary

• If applying additional commercial nitrogen, Be careful! Grass will become more competit ive.

• No enough N=weak stand and invite for competit ion from weeds!

Laboski C.A., Shelley, K.B. 2013. “Soil Fertility Guidelines for Pastures in Wisconsin” University of Wisconsin-Madison. Extension Publication A4034.

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Nitrogen Management in Pastures• Timing

• For pasture grass stands, apply up to 130 lbs N/acre for soils with 2-9.9% OM

• Apply in split applicat ions:• 40-80 lbs early June• 40-80 lbs early August

• Caution- nitrate poisoning• Volatilization- apply before a light

precipitat ion event.

Laboski C.A., Shelley, K.B. 2013. “Soil Fertility Guidelines for Pastures in Wisconsin” University of Wisconsin-Madison. Extension Publication A4034.

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Phosphorus

Laboski C.A., Shelley, K.B. 2013. “Soil Fertility Guidelines for Pastures in Wisconsin” University of Wisconsin-Madison. Extension Publication A4034.

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Nutrient Removal

• 1 ton/ac of pasture/grass hay removes 55 lb of K2O (plant available K)

• A 3-ton harvest =165 lb K2O removal in one year!

• Equivalent to ~ 266 lb ofpotash/A

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Manure Applications

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Manure Crediting

Laboski C.A., Shelley, K.B. 2013. “Soil Fertility Guidelines for Pastures in W isconsin” University of Wisconsin-Madison. Extension Publication A4034. Laboski C.A., Peters J. 2012. “Nutrient application guidelines for field, vegetable, and fru it crops in Wisconsin” University of Wisconsin-Madison.Extension Publicat ion A2809.

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SnapPlus for Pasture Nutrient Management

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SnapPlus for Pasture Nutrient Management

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SnapPlus for Pasture Nutrient Management

N-P-K= 60-30-70 lb/ac

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SnapPlus for Pasture Nutrient Management

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SnapPlus for Pasture Nutrient Management

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SnapPlus for Pasture Nutrient Management

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Runoff Risk Advisory Forecast

http://www.manureadvisorysystem.wi.gov/runoffrisk/index

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Interested in LearningMore?

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Daniel H. Smith, CCASouthwest Regional Specialist

Nutrient and Pest Management ProgramUW-MadisonCALSandDivisionof Extension

Email:dhsmith@wisc.edu Phone:608-219-5170

Twitter: @agronomybadger

Questions?

Thanks!

Disclaimer: Any use of trade names is for descriptive purposes and does not represent an endorsement by the author.

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