Cover Crops at Dakota Lakes

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1 Cover Crops at Dakota Lakes Matt Hansen Background Currently planted after wheat harvest in the fall at Dakota Lakes. Species determined by following crop Grasses ahead of legumes/broadleaves Legumes/broadleaves ahead of grasses Cover crops can have varying effects on the following crop yield 1

2 Cover Crop Advantages Agronomic Advantages Weed control Nutrient cycling Build N (legumes) Store N to prevent leaching (grasses) Improve compaction issues Reduce runoff and erosion Forage options Cover Crops as Forages High protein values through the fall. Legumes Broadleaves High yields late in the fall. Cool season crops Decreased feed costs Winter feeding accounts for a large % of beef cattle production costs. Grazing corn stalks is already a common practice in South Dakota 2

3 Overview Forage Value Yield Protein Fiber Soil Effects Water Nitrogen Corn Effects Yield Protein Economics Cover Crops At Dakota Lakes 6 Legume Mixes Mix 1 Chickling vetch, cowpea, lentil, flax (VC) Mix 2 -Mix 1 + Rape (VC+R) Mix 3 Chickling vetch, field pea, lentil, flax (VFP) Mix 4 Mix 3 + Rape (VFP+R) Mix 5 Field peas, soybeans, flax (FSF) Mix 6 Mix 5 + Rape (FSF+R) 3

4 Cover Crops at Dakota Lakes 5 monocultures + Mix Oats Foxtail Millet Lentil Forage Radish Cowpea Mix of the above (Mix) Forage Evaluation 4

5 Cover Crop Average Yields 1-Oct 1-Nov 1-Dec lbs/acre VC VC+R VFP VFP+R FSF FSF+R Oats Millet Lentil Mix 2010 Crude Protein Levels 1-Oct 1-Nov 1-Dec % Crude Protein VC VC+R VFP VFP+R FSF FSF+R Oats Millet Lentil Mix High quality 3 rd cutting alfalfa 25% CP 5

6 Average NDF % 1-Oct 1-Nov 1-Dec % NDF VC VC+R VFP VFP+R FSF FSF+R Oats Millet Lentil Mix High quality 3 rd cutting alfalfa % NDF Rape mixes %NDF in 2010 and 2011 % NDF VC+R VFP+R FSF+R 1-Oct 1-Nov 1-Dec Very little rape emerged in 2010 (<5% biomass) while there was a large amount of rape present (80%+ of biomass) in most plots in

7 Grazing/Feeding Concerns All crops are suitable for grazing Brassicas can cause bloat Introduce to livestock slowly or supplement with other feed Chickling vetch seeds contain neurotoxins Don t allow plants to reach seed set Soil Effects 7

8 Soil water Soil water content 0-3 ft 4-Nov 29-Apr Crop inches rank inches rank Gain/Loss Check Radish Check Oats Cowpea Lentil Mix Millet VC+R VFP+R FSF+R VC FSF VFP Soil water content and inches Nov 29-Apr 0.84 Oats Millet Lentil Cowpea Radish Mix Check 1 VC VC+R VFP VFP+R FSF FSF+R Check 2 8

9 Soil Water High yielding crops used the most water in 2010, but refilled over the winter to levels close to or above check levels. Crops with more surface residue added water over the winter, likely from snow catch. Mixes had more available water in the spring than monocultures even though they had the lowest fall water levels. Soil and Aboveground Nitrogen Soil NO -3 -N lbs/acre 0-3ft 29-Apr Biomass Crop 4-Nov 29-Apr Change Biomass lb/a N lb/acre C:N ratio VC :1 VC+R :1 VFP :1 VFP+R :1 FSF :1 FSF+R :1 Check :1 Oats :1 Millet :1 Lentil :1 Cowpea :1 Radish :1 Mix :1 Check :1 9

10 Nitrogen Movement All crops had less N going into the winter than the checks. All legume mixes gained soil N over the winter. Crops with C:N ratios of 20:1 are expected to release N to plants the following year. Legumes in this trial should release some N from aboveground biomass. Corn Effects 10

11 Corn Effects Cover crop plots planted to corn in 2011 with 2 nitrogen rates 0 lbs N/a 75 lbs N/a Recommendations for 150 bu/a of corn were lbs/a Rate kept low so cover crop effects weren t masked Corn Effects Green Color Yellow Color 75 lbs/a N 0 lbs/a N Larger Dented Smaller Dough Stage 11

12 Corn Yield 0 lbs N/a Difference 75 lbs N/a Difference Crop Difference Crop bu/a from check bu/ac from check Average from check Check Mix Radish Cowpea Lentil Oats Millet Average Check had significantly higher yields than all cover crops. Mix had significantly higher yields than monocultures. Corn Yield 0 lbs N/a Difference 75lbs N/a Difference Crop Difference Crop bu/a from check bu/ac from check Average from check VFP+R VFP FSF+R FSF VC VC+R Check Average Check had significantly lower yield than cover crops 12

13 Corn Yield and Grain Protein % Grain Protein Crop 75 N Yield 0 N 75 N Difference VFP+R FSF+R VC FSF VC+R VFP Check Check Mix Cowpea Radish Oats Lentil Millet % protein is expected at optimum N levels. N deficiency All plots showed visual symptoms of N deficiency. Plant tissue samples had lower nitrogen concentrations than required for optimum yields. Yellowing Optimum level 0 N 75 N V6 3.5% % % Silk 2.7% % % Flaring N deficiency in plots 13

14 Corn N bu/acre Corn Yield vs Grain Protein 0 N yield 75 N Yield Linear (0 N yield) Linear (75 N Yield) Grain Protein Economics Seed Cost Average Top Forage 75 N Yield Income Gain or loss over check $/acre Yield lb/a Gains $/a* bu/a Gain/Loss Corn** No grazing w/grazing Check 1 $0 0 $ $0 $0 $0 VC $ $ $69 $30 $80 VC+R $ $ $46 $3 $52 VFP $ $ $39 $7 $57 VFP+R $ $ $87 $52 $110 FSF $ $ $62 $33 $74 FSF+R $ $ $72 $39 $85 Check 2 $0 0 $ $0 $0 $0 Oats $ $ $57 -$71 -$30 Millet $ $ $93 -$101 -$66 Lentil $ $ $93 -$143 -$100 Cowpea $ $ $57 -$93 -$81 Radish $ $ $79 -$100 -$89 Mix $ $ $76 -$130 -$95 *-assumes 40% grazing efficiency with 25 lbs dry matter intake and $0.90/day/head rent **-assuming $6.00/bu corn price 14

15 Economics All legume mixes made were profitable with no added income from grazing. All monocultures were not profitable, even with grazing income. As grain prices fluctuate the profitability of these crops will fluctuate as well. Grazing Effects on Corn Grazing will speed up mineralization of N N is available to following crop which may increase yield Grazing will decrease ground cover Could decrease snow catch and spring soil moisture which could hurt yields Residue may disappear sooner in the summer, potentially hurting yields Ground will warm up sooner, speeding seedling development and possibly increasing yields. 15

16 Summary All the crops in this trial, except cowpea, should provide nutritious t livestock feed into December at least. The legume mixes in this trial had enough benefits to negate the need to graze them to justify their planting. Monocultures produce less feed and negatively effect corn yields. Mixes with chickling vetch and field peas provide large amounts of quality feed and improve corn yields. The End 16