I ~ L-907 KEYS TO PROFITABLE GUAR PRODUCTION R. J. Hodges, Murray L. Kinman, Norman W. Brints, Emory P. Boring "' and James R. Mulkey, Jr.* Guar, Cyamopsis tetragonoloba, is a drouth­ textured and sandy loam soils, with good structure tolerant summer annual legume. It was introduced and well-drained subsoils. Guar has been grown into the United States in 1903 from India, where successfully following flax when moisture is avail­ it is grown for exports, as a vegetable for human able on the heavier soils of South Texas. consumption, as cattle feed and as a green manure crop. MOISTURE REQUIREMENTS The guar seed (called a bean) has a rather large The guar plant is drouth resistant; when endosperm which sets it apart from most other moisture is short, growth stops until moisture be­ legumes, 'which have little or no endosperm. The comes available. Such intermittent growth length­ guar endo perm contains galactomannan gum ens the growing season. Peak water use periods which forms a viscous gel in cold water. Perhaps of guar are not as critical as for grain sorghum. the best-known use of guar gum is as a stiffener Guar responds to irrigation since adequate available in soft ice cream, Whip and chill puddings and soil moisture insures maximum production of forage whipped cream substitutes. Such products use the and beans. It is best adapted to areas of 20 to most highly refined food grade guar gum, and 30 inches of annual rainfall. Excessive rain after account for only a small portion of total production. maturity causes the seed to turn black and shrivel Larger volume uses of guar gum are in cloth and which lowers the quality of the beans. Dry fall paper sizing, oil well drilling muds and ore flota­ weather for harvesting is preferred. Profitable seed tion. Heavy imports of guar gum have been from production in areas of high rainfall and humidity India and Pakistan as partially processed endosperm is questionable; however, in such areas it might material. be used as a green manure crop. The meal remaining after the extraction of gum ROTATIONS contains about 35 percent protein, of which about 95 percent is digestible, making it an excellent Guar fits well into a crop-rotating program. It protein supplement for ruminants. It is equal or is a deep tap-rooted summer legume and is an superior to cotton seed meal in amino acids. Enough excellent soil-improving crop. It works well in gum remains in the meal to make it an excellent rotation with cotton, grain sorghum, small grains, feed pelleting material. Toasting improves its vegetables and flax. Increased yields can be ex­ palatability when fed to livestock. pected from crops following guar because of Commercial production of guar began in the increased soil fertility. When used in rotation with early 1950's in South Texas, but the center of pro­ cotton, yield increases of that crop of 15 percent duction quickly moved to the sandy soils of the have been measured. Rolling Plains area of Texas and Oklahoma. Offi­ When harvested for seed, guar still returns cial statistics are unavailable, but Texas farmers considerable dry organic matter to the soil surface plant around 100 thousand acres annually. About as a mulch. half of the planted acreage is harvested. The In a 3-year test at the Chillicothe Experiment remainder is plowed under as green manure for its Station, cotton planted in two-in·four-out systems soil-building properties. produced 250 pounds lint cotton per acre. The SOIL REQUIREMENTS same system, with the two center rows interplanted Guar grows well under a wide range of soil with guar, produced 220 pounds of lint cotton and conditions. It performs best on fertile medium- 500 pounds of guar for a cash advantage exceeding $15 per acre. ·Respectively, Extension agronomist, Texas A&M University; research agronomist, Crops Research Division, Agricultural SEEDBED PREPARATION Research Service, USDA; Extension area farm management Prepare the seedbed for guar the same as for specialist and Extension area entomologist, Vernon, Texas and assistant professor in charge, Texas A&M University cotton, com or grain sorghum. It should be firm, Agricultural Research Station at Chillicothe. free of weeds and the row surface should be slightly 13.17 Texas A&M University • Agricultural Extension Service • John E. Hutchison, Director • College Station to well above general ground level to facilitate Seeding rates, based on percent germination to harvest. Plants on slightly raised beds after the assure a maximum of five plants per linear foot final cultivation insure maximum recovery of low­ of row, are suggested. Broadcast plantings are not set beans at harvest. Guar usually is planted in recommended where moisture is insufficient to 36 to 40-inch rows; however, row spacings of 10 to support the greater plant population. 20 inches might increase yields if moisture is Guar should be planted I to I Y2 inches deep. adequate. PLANTING EQUIPMENT QUALITY SEED Guar usually is planted with equipment em­ Use good-quality, preferably certified seed of ployed in planting grain sorghum. Beveled or recommended varieties. Planting seed should be tapered holes on the bottom side of plates crush of high germination, plump, true to variety and guar seed and cause gumming or clogging. Straight free from other crop and weed seed. holes give less problems. Addition of graphite or a dry detergent in the seed box helps avoid the Since the inoculum of the bacterial blight gumming problem. Reduce seed weight on the disease can be seed-borne, the use of certified seed plates by filling the planter box only about one­ to eliminate admixtures of old varieties, Texsel and third of capacity. Groehler, with improved varieties is important. Diseased Texsel or Groehler plants scattered Equipment designed for seeding vegetable or oil through a field can provide inoculum for spread seed crops has advantages for seeding guar. Special of the disease. New guar varieties are resistant, adapters designed for conventional planter boxes in but not immune, to the disease. -seeding oil crops such as soybeans may be suitable also. INOCULATION OF PLANTING SEED RECOMMENDED VARIETIES Inoculate planting seed just before planting with The development of disease resistant vanetIes a special guar inoculant or the cowpea (Group "E") has stabilized and increased sufficiently to allow inoculant. Sunlight, heat and excessive drying will guar to become a crop of economic importance impair or destroy effectiveness of the bacteria. when adapted. During seasons of normal rainfall, Properly inoculated guar will fix atmospheric these improved varieties permit production of nitrogen in amounts similar to cowpeas or other maximum yields partially resulting from improved legumes. For this reason, crops following guar in harvest efficiency because the pods are set higher rotation generally benefit from the residual nitro­ above the ground level. gen. Brooks, released in 1964, was the first improved variety. It replaced Texsel and Groehler and has PLANTING DATES occupied about 95 percent of the acreage since 1966. Plant guar when continuous warm weather is It is a high-yielding variety of known resistance to assured. It has higher temperature requirements the major guar diseases, Alternaria leaf spot and than cotton for stand establishment. For rapid bacterial blight. It is medium late in maturity establishment, soil temperatures at planting time and of the fine-branching growth habit. Small should be above 70 degrees F. A warm seedbed, racemes of medium-sized pods are well distributed adequate soil moisture and warm growing weather on the main stem and branches. Leaves and stems are essential. Seeding dates can range from March are glabrous (free of hair). The seed are of medium to August in the region of adaptation. Optimum size averaging 3 grams per 100. First pods are set seeding dates in South Texas are April IS to May higher above the ground level than those of old 31; in Central West Texas, May IS to July 1. varieties Texsel and Groehler. Although late plantings usually give satisfactory stands, seed frequently mature during lengthy Hall is a moderately late-maturing variety, periods of rainfall, which may cause staining and slightly later than Brooks. It is resistant to bacterial reduction of bean quality. Late plantings may be blight and Alternaria leaf spot. It is considered satisfactory for summer cover or SOil-improving a full season variety. Plants are relatively tall, crops. coarse and possess the fine-branching growth habit. Small racemes of medium-sized pods are well dis­ SEEDING RATE AND DEPTH tributed over the main stem and branches. Leaves and stems are glabrous. Seed are average size The following seeding rates (based on 85 percent averaging slightly less than 3.0 grams per 100. This germination) are suggested: variety appears best adapted to heavier soil types Single rows 4 to 6 lb. per A. and higher elevations. Double rows 6 to 8 lb. per A. Mills is an early maturing variety which is Broadcast 10 to IS lb. per A. resistant to bacterial blight and Alternaria leaf spot. Plants are short in stature and possess the fine­ Cultural Practices, Usual Dates, Times Over and Hours' Per Acre branching growth habit. Small racemes of above For Production and Harvesting of Guar average-sized pods are well distributed on the main Cultural Usual Times Hr. per stem and branches. Leaves and stems are pubescent practices dates over A. (hairy). Seed are above average in size, averaging about 3.4 grams per.lOO. In dry seasons; Mills does Chisel or hoeme March - May 1 0.4 Harrow April· May 1 0.2 not grow tall enough for efficient harvest. Yields Bed land April - May 1 0.3 generally are lower than those of Brooks and Hall Knife or sweep beds May 1 0.3 Plant & fertilize .