Capturing Manure s Value March 2008
Outline What are the nutrients in manure worth? Where do you need these nutrients? How do you get the nutrients to where you want them? How do you determine nutrient application rates? Strategies for capturing manure s value
Fertilizer Prices Nitrogen 58 cents per lb of N Phosphorus 60 cents per lb of P2O5 Potassium 43 cents per lb of K2O Sulfur 42 cents per lb of S
Value of On-Farm Nutrients Semi-solid dairy manure = $7.55 per ton Value of manure from one dairy cow for one year = $204 (27 ton/year) Beef cow manure = $10.00 per ton Value of manure from one beef cow for one year = $150 (15 ton/year)
How Do You Discover the Nutrient Needs of Individual Fields? Soil Test
Goals of Soil Testing Estimate the nutrients needed for profitable crop production Gain an understanding of nutrient variability within a field or between fields Track changes in nutrient levels over time Limit environmental effects of applied nutrients
Soil Test Phosphorus Variability from a Wisconsin Dairy Farm Soil Test P, ppm 120 110 100 90 80 70 60 50 40 30 20 10 0 1 2 3 4 5 6 7 8 9 10 11 12 Farm Field Number
Good Fertilizer Recommendations Depend On: A representative soil sample Accurate soil and crop history Good laboratory testing techniques Valid interpretation of results
Sampling Methods Are Critical! The soil sample has to represent the field.
Sampling Pattern for a 15 Acre Field Each sample should be composed of at least 10 soil cores.
Sampling Soils for Testing - Techniques - Take at least ten cores per composite sample Use a sampling probe or auger Sample to plow depth (at least 6 inches) Be consistent in depth of sampling Avoid small areas that are not typical of the whole field: - Dead furrows; lime, sludge or manure piles; animal droppings; fences or roads; previous fertilizer bands; eroded knolls; low spots
Sampling Soils for Testing - Frequency & Timing - Row crops - Every 3 to 4 years, or... - At least once per crop rotation. High value crop - Every growing season. Fall sampling is usually best - Allows more time for lab analysis, planning, fertilizer and lime applications. - Be consistent.
The Soil Test Report Provides: Nutrient recommendations for: N, P 2 O 5, and K 2 O. Nutrient credits (if information is supplied). Lime recommendation. Lab results for: soil ph, organic matter (%), P (ppm), K (ppm). secondary and micronutrients - if requested.
Relationship Between Soil Test and Fertilizer Recommendations in WI Soil Test Category Very Low, Low Optimum High, Very High Excessively High Recommendations Crop removal + Crop removal ½ or ¼ Crop removal None
Soil Test Interpretation Categories Soil Test Level Very High Relative Supply of Nutrients From Soil and Fertilizer Soil Probability of Yield Increase <5% High Soil Fert.* 5-30% Optimum Soil Fertilizer 30-60% Low Soil Fertilizer 60-90% Very Low Soil Fertilizer >90% Nutrients available from soil Adapted from Havlin et al.,1999 using WI interpretations Nutrients required * Fertilizers used at high soil test levels are for starter or maintenance purposes
Is Uniform Manure Application a Problem? Will cows distribute manure uniformly over a paddock? Can you spread manure uniformly?
Where Do Grazing Animals Deposit Manure? Water tanks Feeders Shade
How Much Manure Do Your Animals Produce? Dairy 1400 lb cow 148 lbs/day 1000 lb cow 106 lbs/day 750 lb heifer 65 lbs/day 250 lb calf 21 lbs/day Beef 1000 lb cow 63 lbs/day 1100 lb steer 92 lbs/day 750 lb steer 62 lbs/day 450 lb calf 26 lbs/day
Where Do Your Animals Deposit Manure? In the paddocks Lbs of manure per animal per day times number of days on paddock times number of animals on paddock equals pounds of manure applied to paddock Reduce by the % of time animals are out of paddock Divide by paddock size to get application rate per acre Multiply application rate by nutrient content to get nutrients applied per acre Out of the paddocks, in the lanes, lots, milking areas etc.
Winter Feeding/Manure Strategies Winter in feedlot, spread manure Outwinter on a sacrifice paddock Outwinter on multiple paddocks
Next Year Forage Yield With Different Winter Feeding/Manure Strategies Year of Study 2004 2005 Treatment Forage Dry Matter Yield lbs/acre Control 1585 1070 Manure 2760 1190 Bale Grazing 3720 3410 Bale Processing 4710 4940