Nitrogen Release from Cover Crops & Supplemental Fertilizers

Transcription

1 Nitrogen Release from Cover Crops & Supplemental Fertilizers Nick Andrews 1 and Dan Sullivan (Oregon State University Extension) 1 North Willamette Research & Extension Center (503) nick.andrews@oregonstate.edu

2 Application rate Guaranteed analysis Nitrogen mineralization Soil health Measure biomass Lab analysis Models and monitoring Monitoring

3 3080 downloads, about 200/month

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5 Fertilizer N Mineralization 120 Calculator 120 Full Season PAN (% of amendment N) full-season estimate Amendment Total N (%) Broiler litter Dairy solids Rabbit manure Yard trimmings Specialty products Gale et al. (2006). J Env Qual 35: PAN (% of amendment N) Specialty Products include 0 Calculator predicted full season Calculator predicted 28 days Amendment Total N (%) Fish meals Alfalfa meal Fish bone meal Soybean meal Blood meal Meat & bone meal Corn gluten meal Kelp meal Bone meal Feather meal Sol. Seaweed Extract Seabird guano

6 Cover Crop N Mineralization PAN (% of cover crop total N) Vetch + Phacelia Mix Vetch + Oat Mix 28 d Cover crop mix total N (% of dry wt) 70 d Equation: Vigil and Kissel (1991) SSSAJ 55:757

7 Apparent N Recovery Amity silt loam (Mollic) Aloha silt loam Canderly sandy loam Week 4 Week 10 VK Equation Week 4 Week 10 VK Equation Week 4 Week 10 VK Equation Cover Crops tested at mid vegetative and flowering GS Oats Cereal Rye Phacelia Common Vetch Crimson Clover Cover Crop % N

8 OSU Calculator Equations PAN estimate (% of fertilizer N) 100 VK equation cover crop Cover crop Incubation (70d) 70 d 28 d 20 0 "Stable" Compost Organic input N (% dry wt)

9 Cover crop sampling

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11 Handling Samples 1. Mix, remove soil and tear apart large plants. 2. Weigh field sample 3. Select 1 lb (fresh wt.) subsample 4. Package to avoid wilting or molding 5. Send sub sample to lab that will: a. Dry and grind full sample b. Report total %N and % dry matter

12 smallfarms.oregonstate.edu/calculator

13 Cover Crop Analysis & PAN

14 Cost Comparisons

15 Nutrients Provided

16 Idaho Amber Moore UI Irrigated farms in semi arid regions extension.uidaho.edu/nutrient/cc_calculator/cc_page.htm

17 Hawaii Ted Radovich and Archana Pant, UH Collecting data from low and high elevation tropical climates Planning to incorporate models into a calculator for HI

18 David Brown: Mustard Seed Farms 80 ac organic fresh vegetables This year I reduced my fertilizer bill about 60% by working with Nick and Dan and still got great yields This project helps me evaluate my cover cropping program

19 Brian & Jason Montecucco 600 ac (15 COG) fresh vegetables Jason Montecucco Dan Sullivan We have areas on our farm that need organic matter to rebuild the soil from years of intensive farming. We want to use cover crops to prevent nutrients from leaching and capture nutrients essential to plant growth.

20 Soil nitrate N vs. table beet yield Table beet yield (Mg/ha) MF Farm Fallow Fallow + feather meal Phacelia Vetch (PV) PV + feather meal Rye Vetch (RV) RV + feather meal Vetch (V) V + feather meal Soil nitrate-n (mg/kg) on May 18, 2009

21 Sauvie Island Organics 20 ac organic fresh vegetables ~400 CSA members, 25 restaurants Kristin Pool Scott Latham "We didn t give our cover crops enough N credit. The Calculator showed us we were getting twice the N we thought. Now, no N is applied to our head lettuce, we get the same yield and save $275/ac on fertilizer" We invest our savings in additional N to our broccoli field and get higher broccoli yields.

22 Organic Fertilizer and Cover Crop Calculator Impacts >2,400 registered users from every US state and 47 countries 36% farmers 39% other ag professionals 17% students 7% gardeners Estimated $2 million annual economic impact

23 Future work? Outreach and Extension Conferences and workshops Improve Extension & NRCS technical information about cover crops and nutrient management Improve cover crop establishment in marginal conditions (i.e. relay seeding, compost applied with seed, etc.) Cover crop variety trials Increase communication between ARS and Extension & farmers Research Degree day sensitive N mineralization models Regional predictions of cover crop N mineralization Cover crop breeding Nick Andrews 1 and Dan Sullivan (503) nick.andrews@oregonstate.edu