ETBLUVER ‘Contents SPECIES AND VARIETIES _ _ _ _ _ _ _ _ _ _ _ _ ____________ _ _M __________ _ _ 3 WHERE SWEETCLOVER snows ____ _ _e ____________________ _ _ 4 l CULTURAL PRACTICES ____________________________________ __ 4. Inoculation _________ _ _e ____________________ _ __ _ _ _ _ _ _ _ _ _ _ _ 4 Planting Dates _________________ _ _' _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 5 Seeding Rates ________________________________________ _ _ 5 Method of Planting ____________________________________ _ _ '5 Fertilizer _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 5 Weed Control _________________________________________ _ _ 6 USES OF SWEETCLOVER . _ _ . . _ . _ _ _ . _ _ _ . _ _ _ _ _ _ _ _ _ _ _; _ _ _ _ _ _ _ 6 ‘ Hay _j _________________________________ _; ______________ -. 6 Pastures _____________________________ g _ _ . _ _ _ _ . _ _ _ _ _ _ _ _ _ 6 Silage ________________ _ _i _______________________ _ _~ _ _ _ _ _ _ 7 Seed _________________________________________________ _ _ 7 Combine Trouble Chart . _ _ _ _ _ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 8 In a Cropping System _ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ _ 9 DISEASES AND INSECTS ......................... - t ....... - - 10 i Acknowledgment Most of this bulletin is adapted from) Bulletin 791, Szoeetclover in Texas, by R. i formerly associate professor, Department; ronomy, now assistant dean of the S »~ Agriculture. i GRDWITNB IN TEXAS LEE COFFEY BEN SPEARS E. M. TREW Extemion Agronomixt: TEXAS A. 8: M. COLLEGE SYSTEM GREATEST VALUE OF SWEETCLOVER is for ‘Are and soil improvement. Sweetclover is g y adapted and, like other legumes, it util- itrogen from the air. A good crop of V lover may add many pounds of nitrogen soil and improve the tilth, aeration and 5 Water intake. f" AND VARIETIES e annual white.-flowered sweetclover, Titus alba annua, is the type most common exas. Only two varieties, Hubam and (nna, are planted, and over 95 percent acreage of annual white-flowered sweet- is in Hubam. Many Texas seed grow- roduce Hubam seed, and large quantities old out-of-state. Hubam is grown on a ' acreage throughout-the Texas blacklands. ts into the cropping system of this area r than the biennials because cotton root ind late summer drouths limit the areas 1e biennials can be grown. Although sub- to cotton root rot, Hubam usually matures the organism causing the disease can A e the plants seriously. If used as a green ‘ure crop, it may aid in controlling cotton rot. However, some experimental tests conflicting results. loranna produces about the same yields acre as Hubam. It is superior to Hubam u the Port Lavaca area south since it furn- earlier grazing and matures 1 month r. Its early growth habit makes it valu- "for use in wind strips in the blow sand p of South Texas. In North Texas it res at approximately the same time as am and neither ythe seed nor the plants be distinguishedi “Certified seed of Flor- fa should be purchased when possible. Annual yelloiu-flowered sweetclover, Meli- .~ indica, often called sour clover, seldom reaches a height of 3 feet while Hubam often is 6 feet tall. Melilotus indica matures very early, but the forage is not palatable to livestock and this clover should not be used for grazing or hay. Floran.na eventually may replace it in much of South Texas. Melilotus indica has a weak root system and produces less top growth than other adapted sweetclover varieties. It often grows along the roadsides in Area 3, shown on the map below. Biennial white-flowered sweetclover, Meli- lotus alba, is not as popular in Texas as the biennial yellow-flowered types. Two varieties, Evergreen and Spanish, are grown but neither is seeded on a large acreage. Common white also is planted on a small acreage. Evergreen would be an especially desirable variety if the Areas of adaptation of sweetclover in Texas. Area 1, not generally recommended; Area 2, biennial white, biennial yellow, annual white (Hubam) ; Area 2-N, spring planted; Area 2-8, fall planted; Area 3, annual white, annual yellow; Area 4, not recommended except under irrigation. seed were not so difficult and expensive to harvest and if it were more disease resistant. It begins blooming at the base of the plant, and 6 to 8 weeks may elapse before the top has finished blooming. Evergreen is highly suscep- tible to southern anthracnose. Biennial yellow-floioered sweetclover, Me- lilotns officinalis, is the most popular biennial type in the State. Madrid is the only variety grown on a large acreage, but seed of common yellow sweetclover occasionally are planted. Madrid was tested in 1927 at the Denton Ex- periment Station where recommendations for its general use first originated. It rarely ex- ceeds 4 or 5 feet in height while the biennial white-flowered types may reach a height of 8 feet. Madrid produces a better forage than the white-flowered species because it is leafier and has finer stems. It produces a high yield of forage, and its seedling vigor gives it a com- petitive advantage over other vegetation. Since the seed mature fairly uniformly over the plant, they can be harvested mechanically. WHERE SWEETCLOVER GROWS Sweetclover has been tested widely under many environmental conditions in Texas. It is not generally recommended in the sandier soils of Area 1. (See map, page 3.) Sweetclover thrives best in well-drained soils high in lime, phosphorus and potash. Hubam and the bien- nial varieties are well adapted to Area 2. The tight, hard soils in the western part of Area 2 are usually too drouthy for sweetclover. In Comparative top growth in inches of Hubam and Madrid siveetclover 80 days after planting in Central Texas. 4 Second-year growth of Madrid sweet a biennial type. areas where water becomes a limiting. sweetclover should be planted in 36 to rows and cultivated. Large acrea M elilotas indica and Hubam are grown in 3. Poor drainage often limits the grol sweetclover in the eastern half of Area ’ drouth has the same effect in the westerlii M elilotns indica grows better than other g ties of sweetclover in acid soils where no applied. Poorly drained soils, drouth diseases seriously limit the use of bienn‘ Area 3. Sweetclover is not generally I mended in Area 4. Moisture is the w factor in its growth in this area. CULTURAL PRACTICES Sweetclover often is planted in combiP with another crop. The object of this tw] system is to obtain an extra crop from the and to keep down weeds in the young clover. I Inoculation A strain of bacteria _lives on the legumes in clumps (nodules), and these b A take nitrogen out of the air and fix it i" Sweetclover requires a different strain A teria than legumes such as vetch or peas. y small quantities of bacteria are present, ilittle nitrogen is fixed. Sweetclover oc- ally makes more growth the second time lanted in a field than the first since larger ities of the nodulating bacteria are avail- Sweetclover seed should be inoculated to planting unless it or alfalfa was grown i: land during recent years. Commercial lants are available from most seed com- ls and are highly effective, easy to use and 'vely inexpensive. Directions for using the lant are on the containers. ing Dates iennial varieties may be planted in August {September under irrigation on the High is. Otherwise, sweetclover should be spring- ed in late February or early March in A 2N, fall or spring-planted in Area 2S and lanted in Area 3. In these areas it often anted with oats for grazing. The oats make g grazing until late spring, when the clover peady to supply grazing. The practice of ting sweetclover with small grains for ing is not too successful in rainfall areas of inches or less. ing Rates The seeding rate depends upon factors such ermination of the seed, climate, companion s, row width desired and the use to be made the clover. Clover seed may be hulled, un- i’? ed or scarified. It is important, that trified seed be planted if a good stand is tired immediately after planting. However, scarified seed come up over a long period of e, and less risk from unfavorable weather is olved when they are used. In general, the owing seeding rates of high-quality seed are mmended per acre, but these rates should gincreased under especially favorable en- fnments and decreased in the drouthy lions: Rows 36 to 42 inches wide—2 to 3 pounds 3 Rows léf-to 16 inches wide—4 to 5 pounds Overseeding on small grains—8 to 10 §unds Drilling alone—-12 to 15 pounds Preparing sweetclover land for planting a spring-planted crop. One tractor is shredding clover, another bedding the land and still an- other is rebedding it. Method of Planting Sweetclover seed should be planted approxi- mately 1/2 inch deep on a firm seedbed. When planted with small grains, a drill with a small- seed attachment is desirable. The downspouts from the small-seed box may be attached to the rear of the disc boot and the seed allowed to fall behind the disc and then covered with a chain drag or press wheel. Many farmers plant small grain with a drill and then overplant with the same drill. Once sweetclover has produced seed, volunteer stands may come up for several years. Fertilizer Since sweetclover grows under a wide range of soil and climatic conditions, the soils vary widely in their need for fertilizer, even on the same farm. Maximum yields cannot be obtain- ed unless fertilizer is used in combination with good management practices. Sweetclover has a high requirement for both calcium (lime) and phosphorus. It cannot be grown success- fully on soils which remain strongly acid or deficient in either of these minerals. Soil tests should be made before planting sweetclover. Your county agent-can tell you how to obtain a soil test. When sweetclover is planted on soils high in calcium (such as the Blacklands of Central Texas), it is important to place the superphosphate in bands rather than broad- cast. These bands of fertilizer should be ap- proximately 2 inches below the seed. Rear view of grain drill for planting oats and sweetclover in one operation. The sweet- clover seed fall behind the opening disc and are covered shallower than the oats. Weed Control Occasionally it may be necessary to use herbicides to control Weeds in sweetclover. Sweetclover is susceptible to most herbicides and serious injury may result from over-treat- ment. Amine salts of MCPA and DNBP are less likely to injure sweetclover than 2,4-D. MCPA or 2,4-D at 1/8 to 1A; pound in 5 to 20 gallons of water per acre, or DNBP at 3A to 1 pound in 3O to 50 gallons of water per acre will control most broad-leaved weeds in sweetclover. These chemicals should be applied only when the weeds are in the seedling stage. Herbicides should be used only when the weed infestation is serious enough to result in. a reduction of sweetclover stands. USES OF SWEETCLOVER Hay Sweetclover hay is high in protein and often is more difficult to cure than most grass hays. If the hay is cut too early in the season, the moisture content may be so high that it will be difficult to cure properly. Improperly cured sweetclover hay may mold and contain di- coumarin which reduces the clotting power of the blood. Cattle fed this type of hay sometimes bleed to death from slight wounds or internal hemorrhages. Dicoumarin is not evident by visual examination of the hay. Cattle should not be fed large quantities of sweetclover hay just before dehorning, calving or a short time after calving. 6 The plants are larger the second year, wig Sweetclover should be harvested for g when the first blooms appear. The plant become coarse and "stemmy if harvesti delayed until full bloom. so Hay from biennial sweetclover is usual higher quality the first yearlthan the s larger proportion of coarse stems and a s a proportion of leaves. Fall-planted biennialsi be harvested more than once in a season; they usually are grazed until early spring} a hay crop is harvested in June when We, conditions permit. Spring-seeded bien‘ should be harvested in late summer or early l after the plants have had an opportunit build up root reserves. It occasionally is 1 sible to obtain two cuttings of hay from sec year clover or one cutting for hay and this seed crop. i Ji Pastures Sweetclover furnishes good grazing int l areas where it is adapted. It often is plan for this purpose with small grains. Lives _ graze the small grain until late spring whet ceases to grow rapidly, and then the clo usually furnishes excellent grazing. In g Texas Blacklands, small-grain varieties 0 a narily cease to produce much forage after i 1 to May 15, while Hubam may continue produce for another 6 or 8 weeks. Sweetclo and small grain sown in Johnsongrass fie can produce excellent grazing. Biennial Va ties are used with cool-season perennial gras as an irrigated pasture mixture for the H’ Plains. ' Young dairy animals graze this sweetclov pasture. sweetclover field which has been wind- j» and is being harvested with a combine ' h has a pickup attachment. jCattle do not graze sweetclover readily pil they are accustomed t0 its rather bitter i e. Young sweetclover plants are high in lsture and protein. Mature cows usually do er on sweetclover than younger stock. eetclover alone is not highlydesirable for zing since cattle need nonlegume hay or the other form of dry matter to utilize it Yziently. Sweetclover will furnish more Jzing if the plants are maintained at a height 8 to 12 inches’. ~= e Sweetclover silage is equivalent to other i me silage if the plants are harvested When if first blooms appear. Spring growth of ieetclover may be used more efficiently as lge than as hay because it often is difficult cure hay in the spring. Since prebloom etclover has a high moisture content, the should be allowed to wilt slightly before iling. However, it should not become dry or l forage will be spongy, difficult to pack and ihaps spoil. When sweetclover alone is to iused for silage without wilting, 80 to 100 nds of molasses or 150 to 200 pounds of und corn or 8 to 10 pounds of sodium meta- A lfite should be added for each ton of green terial. If pats or barley are growing with sweetcloveir, the mixture should be cut when i grain is in the dough stage and in most es neither preservative nor wilting is neces- . Because of the possibility of dicoumarin being formed, sweetclover should be packed firmly to avoid molding as it goes into the silo. Seed Yields of seed are seldom below 125 pounds per acre and often may be as high as 600 pounds. There are approximately 260,000 seed per pound. Sweetclover seed mature over a period of 2 weeks or more. Harvesting should take place at the stage of maturity when a max- imum yield of high-quality seed can be obtained. Sweetclover is either windrowed and then com- bined or combined direct. Less shattering takes place if windrowing is done when the atmos- pheric humidity is high. The humidity is high- est at night or near sunrise and lowest in the afternoons. Windrowing is most successful prior to 9 A. M., especially after heavy dews. Plants usually are cut for windrowing when approximately 60 percent of the seed have turn- ed black or brown. Clover combines best follow- l“ ing 4 or 5 days of sunny weather. Combining direct is rather difficult since many of the seed will be green or immature. If the seed are left until they are fully mature, there is a loss from shattering. Seed combined direct usually should be spread on a wooden floor to a depth of 4 to 6 inches, and it may be necessary to stir them at 3 to 4-hour intervals until no moisture or heat is evident. Sweetclover is fairly easy to combine if it is windrowed. The stalks usually are cut high and the swath stays on top of the stalks. Some combine operators use a pickup attachment on the combine while others run the cutter bar below the windrow and pick up seed in this manner. It is not necessary to set the combine to turn out only cleaned or hulled seed. The ~ cylinder speed should be approximately 1,600 r.p.m., which is slightly faster than usual for combining grain. The cylinder and concaves should be approximately 1/; to 1/3 inch apart. It may be necessary to change the sieves and those recommendedby themanufacturer should be used. It is important that every combine op- erator have as speed indicator. The correct speeds of the combine cylinder shaft, sieve and straw Walkers are indicated in the instruction manual, and its recommendations for sweet- clover should be followed. COMBINE TROUBLE CHART UNTHRESHED HEADS IN STRAW 1. a. b. Cylinder speed too low Too much clearance between concaves and cylinder ' Insufficient concaves Seed too high in moisture T00 rapid feeding resulting from a high rate of travel THRESHED SEED IN STRAW CARRIED OVER THE REAR OF STRAW RACK a. b. Rack speed too 10W or too high Material chopped up too finely by cylinder Openings in straw rack partially clogged with green material Too rapid feeding resulting in a high rate of travel, thus overloading the rack . THRESHED SEED IN CHAFF CARRIED OVER THE REAR OF THE TOP SIEVE al b. d. e. f. Improper amount or direction of wind blast Material chopped up too finely by cylinder, overloading sieves Openings of sieves plugged up with green material Sieves not opened enough Rear of sieves to low Too much threshed seed in tailings POOR CLEANING a. b. 6. Sieve openings too large Sieves overloaded (1) Feed too heavy (2) Speed too low (3) Straw chopped too fine Wind insufficient orimproperly directed Weeds Elevators clogged CRACKED SEED a. b. c. Cylinder speed too high Threshed seed returned in tailings Insufficient concaves and cylinder clear- ance a Concave or cylinder teeth bent out of alignment If clover seed go through a processing they usually are cleaned with some t , screen-air machine and then run ov scarifier. The scarification process dec ' the percentage of hard seed. Seed handl this manner should have applroximate percent germination. Annual yellow-flowered sweetclover, lilotits iriclica, is harvested in essentiall same manner as other clovers. However, is less loss from direct combining. The ance between the cylinder and concavesl not need to be as large, and the cylinder is usually slower. Oats and annual ye flowered sweetclover often are grown in a ture and the sweetclover seed harvested a same time as the oats. A cleaner will sepfl the clover seed from the oats. ‘ Volunteer Hubam plants in small .5 fields usually mature after the small grain Comparative top arid root growth of Hu Madrid arid Evergreen varieties. i, . Comparative root growth of an annnal ubani) and biennial (Madrid) variety. en combined. The plants are small and often ye combined direct. Yields of 100 to 150 funds per acre may be obtained under these nditions. These fields usually are harvested then 90 percent of the seed turn brown or lack. p Experimental tests indicate that seed yields some varieties may be increased as much as 0 percent if adequate pollinating insects are esent. The biennial species are more likely p» have poor seed set than is Hubam. M eiilotns " icia is self-fertile and produces a full crop of ~ Add without the aid of pollinating insects. The coneybee is regarded as the most valuable of e pollinating insects. One hive or more of oneybees per acre often is desirable. Cloudy, et and muggy weather for prolonged periods r flowering time may reduce the activity of es and cut down the amount of seed pro- uced. Sweetclover produces large quantities F nectar which bees can gather easily. It is he best honey plant in Texas. . During recent years many farmers have pplied desiccants by plane immediately prior i1 seed harvest. Desiccants dry the plants and rapidly and allow direct combining. The ti ost commonly used desiccant consists of 1 to 3 tints of dinitro in 1O to 15 gallons of diesel fuel er acre. This should be applied when approxi- ately half of the seed pods are brown. Com- ining should begin 4 to 5 days after spraying o avoid shattering. Shattering may be severe 1 ithin 8 to 10 days after an application. In a Cropping System Experiment Stations have demonstrated for the past century that sweetclover in a rotation may increase the yields of the crop that follows. The tilth of the soil is improved and the soil is considerably easier to» cultivate. The taproot system of sweetclover, especially the biennial species, penetrates the soil to a great depth. Therefore, sweetclover usually improves the aeration and drainage and also the soil’s ability to absorb and hold moisture. It fixes nitrogen in the plants which eventually may become available in the soil, but the amount is variable and difficult to measure. The tops contain 21/2 to 3 percent nitrogen. Sweetclover does not add any more organic matter to the soil than a nonleguminous crop of the same tonnage. How- ever, its extensive root system may leave part of the organic matter in a more desirable loca- tion than nonleguminous crops such as oats or corn. Where they are adapted, the biennial sweet- clover varieties often produce greater yields of forage the first year than Hubam unless cotton root rot reduces the stand. In addition, they produce approximately 300 percent more roots than Hubam even in the first year. However, Hubam makes a quicker growth than the biennials. Since World War II, high-analysis nitrogen fertilizer has become more readily available to farmers. Many now prefer to use nitrogen fertilizer rather than turning under a crop of In most areas growers debate sweetclover. A crop rotation including siveetclover. A “sweetclover root borer” on a Madrid sweetclover plant. Whether it is economically feasible for farmers to grow sweetclover as a soil-improving crop and not harvest seed or graze the plants for forage. DISEASES AND INSECTS Cotton root rot probably causes more dam- age to sweetclover than any other disease. Hubam and Floranna usually mature before 1O root rot is much of a problem, but seriously reduces the stand of biennial g Biennial varieties are used as annuals southern Blacklands because of root rot. i, is no known method of controlling the y in sweetclover. 3, The insects which attack sweetclov the lygus bug, stink bug, cutworm, grassh Webworm and green cloverworm. The which most frequently damage sweetclov]; lygus bugs and grasshoppers. Frequent should be made in clover fields to determi: degree of infestation. l Refer to Leaflet L-261, “Guide for Co ling Insects on Corn, Sorghum, Small Grail Grasses in Texas,” for controlling insecf tacking clover. l In some years, biennial sweetclover ma come infested with an insect known a sweetclover root borer. The biennial clover acreage has been reduced conside since 1950 when this insect was first’. covered. Infested plants wilt and die d the late summer and early fall of their a year of growth. The above ground symli are similar to those caused by cotton roof However, numerous small holes and small I worms may be found in the roots if the VA clover root borer is present. No lcoé measures for this insect are known. I Additional Information on Sweetclover Agricultural Extension Service B-226 Wheat—A Major Cash Crop in Texas B-819 Irrigated Pastures for South Texas C-297 Liming Soils in Texas L-161 Seasonal Pastures for Year-round Grazing in the Blackland and Grand Prairie Regions L-164 Soil Reaction Preference of Some Plants L-225 Fertilizer Recommendations for the Blackland Prairie, Grand Prairie and Eastern Part of Edwards Plateau L-258 Winter Temporary Pastures Agricultural Experiment Station B-781 Summary of Soil and Water Conservation Research from the Blacklands Ex- periment Station, Temple, Texas, 1942-53 B-791 Sweetclover in Texas MP-90 Soil Conservation Management System for Beef Production in the Blacklands of Texas PR-1439 Effects of Legume Management and Nitrogen on Corn Yields at Denton PR-1458 Importance of Bees in Sweetclover Seed Production PR-1559 Pollination of Hubam Clover by Honeybees PR-1588 Crop Rotation and Cotton Root Rot Control Studies at the Blackland Ex- periment Station, 1948-52 PR-1593 Dairymen Use Clover to Cut Production Costs PR-1'693 Grazing and Feeding Trials, Blackland Experiment Station, 1952-53 PR-1769 Fundamentals of Growth and Management of Soil-improving Legumes PR-1794 Effects of Fertilizer and Row Systems on Corn Yields in Different Crop- ping Systems at Temple, 1953-54 . . . . YOUR COUNTY EXTENSION AGENTS? Ii not. drop by to see them soon. They represent both the United States Department oi Agriculture and The Texas A. 6. M. College System in your county and they can iurnish the latest inior- mation on iarming. ranching and homemaking. Most county extension agents have their oiiices in the county courthouse or agri- culture building. Get to know them and take advantage oi their services. This publication is one oi many prepared by the Texas Agricultural Extension Service to present up-to-date. authoritative information. based on results oi re- search. Extension publications are available irom your local agents or irom the Agricultural Iniormation Oiiice, College Station. Texas. Cooperative Extension Work in Agriculture and Home Economics, The Texas A. & M. College System and t‘ States Department of Agriculture cooperating. Distributed in furtherance of the Acts of Congress of May 8, as amended, and June 30, 1914. 4 1OM—6-57