Pros and cons of grazing cover crops
Transcript of Pros and cons of grazing cover crops
Pros and Cons of Grazing Cover CropsTim Reinbott and Rob KallenbachUniversity of MO
Cover crop Options-Cereals to Brassicas
Cereals
Cereal rye and wheat best if spring cover is required
Spring Oats make good autumn growth but won’t overwinter
Vegetative growth excellent quality feed
Cereal Rye and Other Cereals Rapid Growth During late April and May
Forage Production and Quality of Cereals
Ohio State Univ. Fact Sheet AGF-026-00 David Samples and R. Mark Sule
Carryover of Herbicides On Cover Crops-Kevin Bradley, MU Plant Sciences
Weather is a huge factor. A lot of carryover in 2013, little in 2014 or 2015.
Planting In Fall: Drilling or Overseeding
Timing? Corn About 50% Green, Soybean 75% leaves are Yellow
Overseeding Cereal Rye
Wheat & Cereal Rye Quality
Dec Jan Feb Mar Apr May Jun0
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AD
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Crude Protein in the 20-30 range in the fall and spring
Nutritive value of Oat Forage
Stage Yield CP TDNt/a --------- % ---------
Vegetative 0.6 24 72Boot 1.0 22 70Heading 1.4 18 66Milk 2.1 15 62Late Dough
3.2 11 53
Livestock Gains on Wheat and rye
ADG Total Gainlb/d lb/a
Wheat 1.8 180Cereal Rye 1.6 336
Rye produces more than wheat
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WheatRye
Oats
Use before mid-Jan if fall seeded Strip grazing improves utilization Few varieties with known forage
potential
With All Cereals When Should Grazing Begin?
Grazing should start when forage reaches 8 inches
When Should Grazing Stop?
Livestock should be rotated when forage ht. is less than 3 inches
Regrowth much slower when over grazed
Small Grain Recommendations
Seeded in mid-August for most autumn feed Oats planted at 80 to 100 lb./acre Wheat and cereal rye can be planted at same time but at 100 to
130 lb/acre 50 to 75 lb./acre N at planting Do not graze to a height of less than 3 inches Yields of 1.5 to 3.0 tons/acre common
Annual Ryegrass
Easily established Rapid fall growth Retains green tissue nearly all
winter Remains vegetative into early
May
Annual Ryegrass Establishment
Annual Ryegrass Ready for Grazing
Grazing often can begin 60 days after planting
Rotational grazing a must for best utilization
Graze no shorter than 3” to encourage regrowth
Overseeding Annual Ryegrass
Grazing Management-8 inch and 3 inch Management
Annual Ryegrass Stockpiles Well
Annual Ryegrass Quality
Nov Dec Jan Feb Mar Apr May Jun0
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F (%
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Animal Gains on Annual Ryegrass
Grazing Days ADG Total
Gaind lb/d lb/a
Year 1 95 1.8 511Year 2 83 1.5 314
Winter Kill-Some Varieties
Annual Ryegrass Recommendations
Plant a winter hardy cultivar in late-August at 25 to 30 lb./acre-Marshall and Bounty as examples,
Apply 50 lb./acre of N at planting Apply a additional 50 lb./acre of N in late Feb. Begin grazing when grass reaches 8 to 10 inches Leave a 3 to 4 inch stubble for regrowth –
especially in winter If reseeding is desired, remove livestock in mid-
May
Soybean Herbicides Affect Cover Crop Growth
Many Herbicides Affect Fall Growth-May Want to Consider A Post Emergence Approach
Brassica Forages
Brassicas; Advantages
Rapid growth; capable of producing 3 tons/acre
Handle heat fairly well Continue to grow after killing
frosts Both above and below
ground portions can be grazed
Brassicas
Seeds are small 200,000 per lb
Existing sod, weeds, etc. compete severely
A weak seedling for first 21 days or so.
Brassicas
Strip grazing offers best utilization
Watch for bloat Offer some dry
roughage for stock
Brassica Forage Quality
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Brassicas: Recommendations
Plant from mid-April though mid August at 2 to 4 lb./acre Plant 60 days prior to feed need Control competition for first month after seeding Apply 75 lb./acre of N at planting Do not be fed alone in the diet (bloat and other problems)
In New Zealand Winter Grazing on Feeder Beets and Kale.
Let’s Combine Brassicas and Cereal Crops
Covercrop Legumes
Legumes
Nodules-Symbiotic Relationship Between the Plant and the Bacteria. Atmospheric Nitrogen is Fixed by the Bacteria For Use by the Plant.
How Do You Know A Nodule Is Fixing Nitrogen?
Important to Inoculate
Each Species of Legume has a Different Species of Bacteria
You must match them together.
Legumes-In the fall do not produce much biomass
Develop a rosette but little autumn/winter growth
Fine for cover but not much feed to stock
Excellent quality
Hairy Vetch-in Mid May90% of its growth 2 weeks before flower
Early May Late May
Hairy Vetch Growth Over Time
Adapted from Gallagher, Penn State2007 Hairy Vetch Corn Yield-0 N
Time lbs/acre %N N lbs/acreEarly (May 4) 1,400 3.82 55 113Middle (May 15) 4,300 4.43 190 132Late (May 31) 6,600 4.15 274 140
2008Early (May 1) 3,204 2.49 80 92Middle (May 14) 4,005 2.92 117 121Late (May 29) 4,361 4.55 197 79
Legumes
~90% of growth from early March to mid-May
Yields of 1 to 2 tons/acre******Growth in spring often late enough to interfere with cropping operations
Mean Forage Nutritional AnalysisFrom November-June
Species Crude Protein ADF NDF
%
Arrowleaf clover 24.9 ab 21.5 bc 26.0 cd Field Pea 23.2 b
21.4 bc 30.2 c Cereal Rye 19.1 c 25.1 a
46.4 a Ryegrass 19.1 c
24.7 ab 41.8 b Hairy Vetch 26.4 a 19.7 c
25.1 d
Summer Cover Crops-Sorghums and Millets
Forage Quality of Sorghum and Corn
Strip Killing Sorghum Sudan Into Tall Fescue
Reinbott and Blevins, 1995
Grazing and Haying Restrictions Soybean Herbicides Old Soil Applied Chemistries Such as Dual, Treflan, Prowl-No Restrictions Newer Soil Applied Chemistries-Depends some only 14 days others
never Most Post Emergence Herbicides-Do Not Graze-Basagran the Exception Roundup (Glyphosate)-8 weeks Liberty-Do Not Graze
Corn Herbicide Grazing Restrictions
Dual, Prowl and others no restrictions Atrazine- after 21 days 2,4-D-after 7 days Roundup-8 weeks Liberty-60 days forage 70 days fodder