oas Rial Centos SUSTAINABLE SWEETCLOVER AGRICULTURE MANAGEMENT GUIDES AUGUST 1998 MGID.1 hwide range adap rom denl an ea dow oil m pH of 6 or hi her for its the ccur and has a higher easily decomposable roots to the less easily decompos able tons (Willard 1927) its high lime requirements,it is similar to lespedeza with its ability to tolerate low fertility soils. Crop Rotation Management Sweetclover is a true biennial since it survives only one winter ("Cover Crops Management for No-till Grain Sweetclover often is interseeded into wheat.While Crop Production,"1986). a biennial legume.it can be terminated the following Sweetclover produces more vegetative growth the spring after planting to quicken the rotation back to a first year than most legumes because it grows uninter- cash crop such as grain sorghum or corn.Terminate the rupted we has begun to regrow atter win A1927) the first year and up to five et the yea ar Her gtor prefers to br nadcas tclover is noted best for its ability to i d1 soil structure through its t eme ed dry urea using an air oots penetrate 20 to 30 feet deen into the soil Roots preader.If the field is rotated to grain sorghum the fol- make their greatest depth of growth during the first owing spring.Granzow will disc the clover in early year.Root growth doesn't increase much till August of May and plant grain sorghum later in May.Another the first year.Then the root weight doubles from early option is to summer fallow the clover field in the sec- October to freezing weather with 60-65%of the growth ond year and rotate back to wheat(Granzow,1998). occurring in the top four inches of soil.In the second Paul Burmeister near Claflin,Kansas interseeds year the feeding roots within the top three feet become sweetclover with grain sorghum at planting.Fiberglass more abundant.Nodules are found at all depths. The boxes in every other opening in his drill separate the root weigh year reaches about 900 pounds seed per sare typ above groun growth dur ng the yea al rt in fall of the 993 sweetc 4。 19g2e m ntod and ields het second vear should be done only after a few inche ation without control witho regrowth to ensure that the plants will not out back tclover with herhicide weed control (52 ys 5 again maximum soil improvement is provided when oushels per acre)(on-farm lISA Demonstration the sweetclover is allowed to reach the bloom stage 1991).Weed control options are limited after planting during the second season,plowed under,and rotated to so proper seedbed preparation,later planting,and quick a small grain in the fall. The favorable effects of two mergence of the sorghum and sweetclover are critical years of sweetclover upon soil aggregation last for 2-3 for shading out weeds. vears ("Sweetclover in Kansas."1978).The optimum Page1
SWEETCLOVER AUGUST 1998 MG1D.1 Page 1 SUSTAINABLE AGRICULTURE MANAGEMENT GUIDES Kansas Rural Center Sweetclover has a wide range of adaptation. Sweetclover can obtain phosphorus from relatively unavailable soil phosphates and is able to grow on soils where alfalfa, red clover or white clover often fail. It requires a pH of 6 or higher for proper nodulation to occur and has a higher calcium requirement. Sweetclover is highly sensitive to acid soils. Except for its high lime requirements, it is similar to lespedeza with its ability to tolerate low fertility soils. Sweetclover is a true biennial since it survives only one winter (“Cover Crops Management for No-till Grain Crop Production,” 1986). Sweetclover produces more vegetative growth the first year than most legumes because it grows uninterrupted till freezing weather. Sweetclover resumes growth in the spring later than alfalfa, red clover or alsike clover (Willard, 1927). Sweetclover can grow up to three feet the first year and up to five feet the second year. Sweetclover is noted best for its ability to improve soil structure through its tremendous root growth. Its roots penetrate 20 to 30 feet deep into the soil. Roots make their greatest depth of growth during the first year. Root growth doesn't increase much till August of the first year. Then the root weight doubles from early October to freezing weather with 60-65% of the growth occurring in the top four inches of soil. In the second year the feeding roots within the top three feet become more abundant. Nodules are found at all depths. The root weight the second year reaches about 900 pounds per acre (Willard, 1927). The above ground growth during the second year comes from dormant buds on the lower stem. If sweetclover is cut too short in fall of the first year, regrowth will be prevented and the plant will die. Plowing the second year should be done only after a few inches of regrowth to ensure that the plants will not sprout back again. Maximum soil improvement is provided when the sweetclover is allowed to reach the bloom stage during the second season, plowed under, and rotated to a small grain in the fall. The favorable effects of two years of sweetclover upon soil aggregation last for 2-3 years (“Sweetclover in Kansas,” 1978). The optimum time for plowdown is late April to early May, achieving 80% of the maximum nitrogen accumulated during the season. However, an earlier plowdown helps reduce soil moisture depletion. Delaying spring plowing merely permits the translocation of dry matter from the easily decomposable roots to the less easily decomposable tops (Willard, 1927). Crop Rotation Management Sweetclover often is interseeded into wheat. While a biennial legume, it can be terminated the following spring after planting to quicken the rotation back to a cash crop such as grain sorghum or corn. Terminate the sweetclover only after it has begun to regrow after winter dormancy. Time the termination to optimize the spring growth with the need to conserve moisture for the subsequent crop. Bill Granzow near Herrington prefers to broadcast sweetclover seed 12 pounds per acre on wheat ground in December with topdressed dry urea using an air spreader. If the field is rotated to grain sorghum the following spring, Granzow will disc the clover in early May and plant grain sorghum later in May. Another option is to summer fallow the clover field in the second year and rotate back to wheat (Granzow, 1998). Paul Burmeister near Claflin, Kansas interseeds sweetclover with grain sorghum at planting. Fiberglass boxes in every other opening in his drill separate the sweetclover and grain sorghum seed. Burmeister’s drill has 10 inch row spacings. The seed rates are typically about four pounds of sorghum seed and six pounds of sweetclover seed per acre (Burmeister, 1993). An on-farm trial in 1991 resulted in comparable yields between the sweetclover/grain sorghum combination without herbicides and a control without sweetclover with herbicide weed control (52 vs. 51 bushels per acre) (On-farm LISA Demonstration, 1991). Weed control options are limited after planting so proper seedbed preparation, later planting, and quick emergence of the sorghum and sweetclover are critical for shading out weeds
Page2 Sweetclover Nitrogen Credits alting ina"bleeding disease"in livestock.Gran ek of Ma as during the ir ow pre ave enc urity to as irst yea ng sev has be 160 dry matte r basis on the Gra w farm(Granzow but by July the differe total nit e acre contained in the second yes Soil Moisture growth usually reaches a maximum before the middle of June.The greater the first year's growth,the earlier Sweetclover exceeds alfalfa in its ability to withstand this peak is reached.Sweetclover continues uninter- drought conditions and high temperatures ("Cover rupted growth until freezing weather,while alfalfa and Crops Management for No-till Grain Crop Production. red clover usually bloom and form some seed the first 1986).Under the stress of drought in Kansas in 1989 year after fair vegetative growth. This difference an on- stration reveale grain sorghum fol allows swee ing fallow yi lded more than s Rural Ce An early spring pl er will 1927 on the fo following crop ("Sweetclover in Livestock Feed Establishment Seeds may be poiso ous to hor Cattle can he Broadcast 10-15 pounds of sweetclover per acre into soned by eating moldy hay.The fungus in moldy hav fall-planted small grains iust before the period of spring can result in external and internal hemorrhages(Duke freezing and thawing.The natural heaving of the soil and James,1981).Poorly preserved silage can also will help cover up the broadcasted seeds.Under favor result in this"bleeding disease."Clover should be wilt- able fall moisture conditions, sweetclover can be ed to 65%moisture before ensiling. Sweetclover drilled at a depth of less than a half inch into a firm grows rapidly in the spring and its palatability decreas see in mid-August at 10 pounds per acre. Fal es as plants grow taller and more woody Sweetclove over generally yie ess than spring 1978). Cattle tire of the taste I swe sweetclove ing often prefer ot Sweetclover more v a this tim nd cat ake ncreas and and lo than alfalfa of Wash th seedlings (Sweetclover in Nebraska."1943) alfalfa with grass pasture fer the Scarification parts,sheep the finer parts (Goldstein 198g Sweetclover can cause bloat but it is less of a risk than Sweetclover seed should be scarified since newly with alfalfa (Sweetclover Production and threshed seed germinates less than 50%of the seed Management,.”1985). with 50-80%being hard seed ("Sweetclover in Bill Granzow,a farmer near Herrington,prefers to Kansas.”1978) graze sweetclover the second spring from late April to the third week in May before turning the cattle onto Varieties Granzo Bloat Guard to preven ng,Gra ve Yellow condit ethcetclorerblod arlier,prod b d ha avo a better th and s the ter oducer than white hlo clover (Willard to preve nold that 1927).Certified Norgold seed will produce a low
Page 2 Sweetclover Nitrogen Credits Sweetclover, when grown for two years, produces the equivalence of 100-120 pounds per acre of nitrogen (“Using Legumes in Crop Rotations,” 1988). First year summer seeding severely reduces the amount of organic matter and nitrogen during spring of the second year, but by July the differences narrow significantly. The total nitrogen per acre contained in the second year's growth usually reaches a maximum before the middle of June. The greater the first year's growth, the earlier this peak is reached. Sweetclover continues uninterrupted growth until freezing weather, while alfalfa and red clover usually bloom and form some seed the first year after fair vegetative growth. This difference allows sweetclover to produce more dry matter and nitrogen in the fall of the first year and have a much higher percentage of nitrogen in the dry matter early in the second year than alfalfa and red clover (Willard, 1927). Livestock Feed Seeds may be poisonous to horses. Cattle can be poisoned by eating moldy hay. The fungus in moldy hay can result in external and internal hemorrhages (Duke and James, 1981). Poorly preserved silage can also result in this “bleeding disease.” Clover should be wilted to 65% moisture before ensiling. Sweetclover grows rapidly in the spring and its palatability decreases as plants grow taller and more woody (“Sweetclover in Kansas,” 1978). Cattle tire of the taste of sweetclover and often prefer other forages. Sweetclover fed to cattle has a laxative effect until it blossoms and at this time cattle increase their preference for sweetclover and make better weight gains. In the dry, wheat growing region of Washington, beef gained a third more weight on sweetclover with grass pasture than on alfalfa with grass pasture. Cattle prefer the coarser parts, sheep the finer parts (Goldstein, 1989). Sweetclover can cause bloat but it is less of a risk than with alfalfa (“Sweetclover Production and Management,” 1985). Bill Granzow, a farmer near Herrington, prefers to graze sweetclover the second spring from late April to the third week in May before turning the cattle onto native grass. Granzow uses Bloat Guard to prevent bloat. After grazing, Granzow will let the sweetclover regrow and under favorable conditions will harvest seed. This land would then be rotated back to wheat. Granzow avoids baling second year sweetclover because the coarse stems are more difficult to cure adequately to prevent mold that produces dicoumarol, resulting in a “bleeding disease” in livestock. Granzow also has put up sweetclover as silage during the third week of May. Granzow prefers sweetclover to have a good bloom and more maturity to assist wilting the forage to get a desired 65% moisture content at ensiling. Sweetclover silage has been tested on a 16% protein dry matter basis on the Granzow farm (Granzow). Soil Moisture Sweetclover exceeds alfalfa in its ability to withstand drought conditions and high temperatures (“Cover Crops Management for No-till Grain Crop Production,” 1986). Under the stress of drought in Kansas in 1989, an on-farm demonstration revealed grain sorghum following fallow yielded more than following sweetclover (Kansas Rural Center On-farm Demonstration, 1989). An early spring plowing of sweetclover will reduce drought stress on the following crop (“Sweetclover in Kansas,” 1978). Establishment Broadcast 10-15 pounds of sweetclover per acre into fall-planted small grains just before the period of spring freezing and thawing. The natural heaving of the soil will help cover up the broadcasted seeds. Under favorable fall moisture conditions, sweetclover can be drilled at a depth of less than a half inch into a firm seedbed in mid-August at 10 pounds per acre. Fall seeded sweetclover generally yields less than spring seeded sweetclover. Summer seeding exposes the sweetclover to more winter kill from winter heaving (Kansas Ag Experiment Station’s Biennial Director’s Report, 1942). Sweetclover and red clover seedlings withstand lower spring temperatures than alfalfa seedlings (“Sweetclover in Nebraska,” 1943). Scarification Sweetclover seed should be scarified since newly threshed seed germinates less than 50% of the seed with 50-80% being hard seed (“Sweetclover in Kansas,” 1978). Varieties Yellow sweetclover blooms earlier; produces less plant matter but more roots; has shorter, smaller stems; withstands drought conditions better during seeding; is a better hay producer the second year; and is also a better seed producer than white blossom clover (Willard, 1927). Certified Norgold seed will produce a low-
Sweetclover Page3 coumarin variety of sweetclover which will help reduce the bitter taste of the clover and the potential risk of Burmeister,Paul."Interplanting of Sweetclover and sweetclover disease ("Sweetclover Production and Grain Sorghum in Central Kansas.1993.Substituting Management,"1985). Publication oject Report 991 enter. licati ansa Granzow Bill 1998 Personal communication REFERENCES Herrington.Kansas. "Cover Crops management for no-till Grain Crop CREDITS Production."1986.University of Missouri-Columbia Extension Division. The author of this publication is Jerry Jost with the Kansas Rural Center. Willard,C.J.1927."An Experimental Study of Sweet Funding for this management guide came from Clover."Ohio Agricultural Experimental Station. SDA's Environmental Quality Incentives Program Additional funding is an Water Farms ct,a as Rural Center in coop (KDHE) un de the n Agency (EPA) Section 319 The U.S Dece artm Duke and James.1981.Handbook of Legumes of hibits discrimination in all its p World Economic Importance. on the basis of race.color.national origin,gender.reli- gion,age,disability,political beliefs.sexual orienta Goldstein,Walter.1989."Thoughts on Drought tion and marital or family status (Not all prohibited Proofing Your Farm;A Biodynamic Approach." bases apply to all programs.)Persons with disabilities Michael Fields Agriculture Institute who require alternative means for communication of program information (Braille,large print,audiotape ete.)should contact USDA's TARGET Center at(202 anagement".1985 720 (volce an ve Extension Service.North Dakota State nati USDA om s rural center On-far nonstration.1989 opportur it and emplover Kansas ag experiment station's biennial director's Report.1942-44 "Sweetclover in Nebraska".1943.University of Nebraska. omotes the lone ople through ec cation. The Rural Center cultivates grassroots supp ort for nublic policies that encourag family farming and stewardship of soil and water.The Rural Center is committed to economically viable.environmentally sound,and socially sustainable rural culture.For more information,contact the Kansas Rural Center at PO Box 133. Whiting.Kansas 66552 or (785)873-3431
The Kansas Rural Center is a private, non-profit organization that promotes the long term health of the land and its people through education, research and advocacy. The Rural Center cultivates grassroots support for public policies that encourage family farming and stewardship of soil and water. The Rural Center is committed to economically viable, environmentally sound, and socially sustainable rural culture. For more information, contact the Kansas Rural Center at PO Box 133, Whiting, Kansas 66552 or (785) 873-3431. Sweetclover Page 3 coumarin variety of sweetclover which will help reduce the bitter taste of the clover and the potential risk of sweetclover disease (“Sweetclover Production and Management,” 1985). Publications Kansas State University Extension has a useful publication entitled “Sweetclover in Kansas,” L-510, 1978. REFERENCES “Cover Crops Management for No-till Grain Crop Production.” 1986. University of Missouri - Columbia Extension Division. Willard, C. J. 1927. “An Experimental Study of Sweet Clover.” Ohio Agricultural Experimental Station. “Sweetclover in Kansas.” 1978. KSU Cooperative Extension Service. “Using Legumes in Crop Rotations.” 1988. KSU Cooperative Extension Service. Duke and James. 1981. Handbook of Legumes of World Economic Importance. Goldstein, Walter. 1989. “Thoughts on Drought Proofing Your Farm; A Biodynamic Approach.” Michael Fields Agriculture Institute. “Sweetclover Production and Management”. 1985. Cooperative Extension Service. North Dakota State University. Kansas Rural Center On-farm Demonstration. 1989. Darrell Park's farm near Manhattan. Kansas Ag Experiment Station's Biennial Director’s Report. 1942-44. “Sweetclover in Nebraska”. 1943. University of Nebraska. Burmeister, Paul. “Interplanting of Sweetclover and Grain Sorghum in Central Kansas. 1993. Substituting Legumes for Fallow in the US Great Plains.” Conference. Rapid City, South Dakota. On-farm LISA Demonstration and Project Report. 1991. Kansas Rural Center. Whiting, Kansas Granzow, Bill. 1998. Personal communication. Herrington, Kansas. CREDITS The author of this publication is Jerry Jost with the Kansas Rural Center. Funding for this management guide came from USDA’s Environmental Quality Incentives Program. Additional funding is from the Clean Water Farms Project, a project of the Kansas Rural Center in cooperation with the Kansas Department of Health and Environment (KDHE), and funded by the U.S. Environmental Protection Agency (EPA) Section 319 Non-Point Source Funds. The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, gender, religion, age, disability, political beliefs, sexual orientation, and marital or family status. (Not all prohibited bases apply to all programs.) Persons with disabilities who require alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact USDA’s TARGET Center at (202) 720-2600 (voice and TDD). To file a complaint of discrimination, write USDA, Director, Office of Civil Rights, Room 326W, Whitten Building, 14th and Independence Ave, SW, Washington, DC 20250-9410, or call (202) 720-5964 (voice or TDD). USDA is an equal opportunity provider and employer