Hayfield Fertility. Travis Harper Regional Agronomy Specialist University of Missouri Extension

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1 Hayfield Fertility Travis Harper Regional Agronomy Specialist University of Missouri Extension

2 Crop Removal Rates When you harvest hay, you are removing nutrients from that soil/field Per ton of hay per acre: 55 lbs N, 13 lbs P, 57 lbs K Average Yield ~2 tons per year 110 lbs N, 26 lbs P, 114 lbs K Fertilizer Cost $150 per acre $75 per ton $45 per 1200 pound bale

3 Types Of Fertility Long-Term Fertility Lime Phosphorus Potassium Short-Term Fertility Nitrogen

4 Long-Term Fertility Replace what s removed by crop Build up soil test levels Only way to know how much is to get a soil test Simply too expensive to apply recommended P and K You MUST replace what s removed by crop Only covers 40-60% of yield potential

5 Soil ph and Liming Extreme ph affects nutrient availability ph less than 5.0 causes aluminum toxicity ph less than 4.5 causes hydrogen toxicity ph for grasses needs to be at least 5.0 For legumes, the minimum is 5.5 or higher If you can only afford to do one thing, lime.

6 Short-Term Fertility Nitrogen There s a difference between nitrogen fertility on pasture and on hayground

7 Nitrogen for Tall Fescue Unfertilized Forage Yield Herd feed requirement April June August October

8 Nitrogen for Tall Fescue Hay Traditional spring fertilization for Hay: - apply nitrogen in mid March - maximizes natural growth curve Forage Yield Herd feed requirement April June August October

9 Nitrogen From Organic Matter This is how you re able to grow grass even if you don t fertilize 20 pounds of nitrogen per 1% per year Average OM 1-3% Available slowly throughout the year To increase organic matter by 1% you have to return 20,000 pounds of grass to the soil per acre per year for 10 years!

10 N 2 Fixation in Mixed Stands Species N 2 Fixed (lb./a) Ndff Year 1 Older (%) Alfalfa Birdsfoot trefoil Red clover White clover (Ledgard and Steele, 1992; West and Mallarino, 1996)

11 Commercial Nitrogen Sources Fertilizer Source Yield (tons per acre) Ammonium Nitrate 4.5 Urea 4.6 Ammonium Sulfate 5.3 Urea treated with Agrotain 4.8 Kallenbach, 2005

12 Urea Apply urea after dew has dried (probably not an issue for March applications) Apply urea right before an expected rainfall event (.25 inches minimum) Otherwise, 30% of nitrogen can be lost in as little as 3 days Agrotain gives you 2 weeks for rain until nitrogen is lost

13 Timing For Cool-Season Grasses: In March, to maximize spring growth After May cutting, if conditions are ideal for a second spring cutting In August, for a fall cutting

14 Nitrogen for Tall Fescue Hay Traditional spring fertilization for Hay: - apply nitrogen in mid March - maximizes natural growth curve Forage Yield Herd feed requirement April June August October

15 Timing For Warm-Season Grasses: Bermudagrass May and every 30 days after Warm Season Perennials When grass is 3 to 5 inches Warm Season Annuals Establishment, after each cutting if a subsequent cutting is anticipated

16 Nitrogen Rates How much hay do you want and how much do you want to spend? Cool-season grasses are responsive to nitrogen up to 180 lbs/a Bermudagrass is responsive to 300 lbs/a + It s best to spread these applications out Remember your crop removal rates

17 Nitrogen or Legumes?

18 Poultry Litter Nitrogen 82 pounds per ton Phosphorus 42 pounds per ton Potassium 54 pounds per ton At current fertilizer prices, that s $106 worth of nutrients Well, actually it s about $81 worth of nutrients

19 Nitrogen in Poultry Litter 82 pounds per ton 10% or 8.2 pounds is inorganic and available immediately 50% or 37 pounds is available during the first year 20% or 15 pounds is available the second year 10% or 7-8 pounds is available the third year The remainder is lost

20 Poultry Litter on Hay Apply based on P need Great for building up P and K Hay is another high potassium crop Hay benefits from having N applied at just the right time Litter may disappoint, likely need N supplement

21 Poultry Litter and Weeds

22 Feeding Hay Back A good portion of N, P, and K in hay comes back out of the cow Feed hay in pastures where it was baled Feed same amount that you took out Spread hay around as evenly as possible You re never going to get everything back

23 Field Renovation and Weed Control Travis Harper Regional Agronomy Specialist University of Missouri Extension

24 Renovation To renew and improve 4 Items Fertility Legume Addition Weed Control Complete Reseeding

25 Soil Fertility Poor soil fertility is often the cause of poor yields, thin stands, legume failure, and plays a major role in weed pressure Test your soil Apply need lime, phosphorus, and potassium

26 Legumes Benefits of legumes Higher yields Improved quality Nitrogen fixation More summer growth

27 Legumes How To Seed Legumes Soil test and apply needed lime and fertilizer Reduce vegetative cover in late fall or winter Select legume Use appropriate seeding rate Get good seed to soil contact Control grass and weed height until legumes are 3-4 inches tall

28 Weed Control In a hayfield, anything a cow won t eat is a weed Weeds may give you a false reading on hay quality Half of weed control is proper soil fertilization and cutting hay at correct time Eventually, we have to make the decision to spray

29 Mowing / Clipping

30 Keep Weeds from Going to Seed Weed Approximate Seeds Produced Per Plant Longevity of Weed Seeds in the Soil (Years) Redroot Pigweed 117, Curly Dock 40, Common Ragweed 15, Foxtail 6, Mullein 223, Musk Thistle 10,000 7 Sericea Lespedeza 1000 / stem 20+ Spotted Knapweed 1, Johnsongrass 80,000 10

31 Remedy Ultra / Relegate / Clear Pasture (triclopyr) Tordon / Trooper / Triumph / Outpost (picloram) Cimarron / Purestand (metsulfuron) 2, 4-D / Weedar / HiDep / etc. (2,4-D) Banvel / Clarity (dicamba) Milestone (aminopyralid) Stinger (clopyralid) Common Pasture Herbicides Crossbow / Candor (2,4-D+Remedy) Surmount (Tordon+Starane) Brash / Range Star / Weedmaster (2,4-D+Banvel) Chaparral (Milestone+Cimarron) PastureGard (Remedy+Starane) Cimarron Max (Cimarron+Banvel+2,4-D) GrazonNext HL(Forefront) (Milestone+2,4-D) Grazon P+D / Gunslinger / Hired Hand (Tordon+2,4-D)

32 Deciding To Spray In pastures, we spray before weeds make up 50% of pasture by weight We are less tolerant of weeds on hay ground than we are in pastures Maybe spray at 25 or 30 percent? Have to sacrifice your legumes Don t let this keep you from spraying

33 Thistles

34 Mechanical Mow within 2 days after the terminal flower head blooms. Problem Flowers over a 7-9 week period! It begins to spread seed about 10 days after first bloom

35 Mowing Timing is important Least destructive to weevils in July Multiple mowings may be necessary 11% killed by single mowing at late bud stage 79% killed by second mowing 4 weeks later (Kansas Study)

36 Fall (Rosette Stage) Spring (Rosette/Prebud Stage) 2,4-D ester (LV4) Banvel Grazon Tordon Cimarron Milestone GrazonNext Herbicide

37 Johnsongrass Sorghum halepense Perennial that grows 6-8 ft tall Warm season grass Prolific rhizome producer Introduced as a forage from Turkey into S. Carolina about 1830 William Johnson Farmer propagated it in Alabama about 1840

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39 The Good Forage Yield Range Ton/Acre Crude Protein % TDN % Johnsongrass Pearl Millet Tall Fescue Hybrid Bermuda Source: Ball et al., 2007 Southern Forages, 4 th Edition Quality Tonnage Persistence Drought Tolerance

40 The Bad Johnsongrass Sorghum halepense Reproduces from seed and rhizomes Rhizomes have been found 5 ft deep Rhizomes can develop within 19 days of seedling emergence 275 ft of rhizomes from one plant 80,000 seeds from one plant that can remain viable for 10 years. Robs desirable species of light, nutrients and water

41 The Ugly Prussic Acid Nitrate Toxicity

42 Cultural Practices for Control in Pastures Mowing/Grazing: Prevents seed production Depletes carbohydrates in rootstocks Rhizome development reduced when the plant height is kept below Heavy grazing for multiple years The growing point sits 4-8 above ground

43 Chemical Control Poast Plus, Assure II, Select & Fusilade in Soybeans Select in Alfalfa Accent & Beacon in Corn Few options for Grain Sorghum Ignite on Liberty-Link Corn Lightning on Clearfield Corn Roundup-Ready in Corn, Soybeans and Alfalfa More options now available in bermudagrass Few options for fescue

44 Rotation / Renovation Rotation to Roundup-Ready crops or crops with registered herbicides Renovation out of infested fescue Spray-Smother-Spray

45 Special Problem Broomsedge Low ph Low phosphorus Poor management Easier to prevent than to cure Promote growth of desired species

46 Complete Pasture Renovation Usually not necessary Replace K-31 tall fescue with other species Weeds so bad it s easier/cheaper to start over than try to control them Before you do a complete renovation, you need to understand why one was needed You need to get the fertility levels right before you reseed

47 Questions? Travis Harper Regional Agronomy Specialist Clinton, MO