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Grain sorghum (Gramineae Sorghum bicolor L. Moench), also called milo, is currently produced in 18 states (figure 1), although production is most concentrated in the central and southern Plains states of Nebraska, Kansas, Oklahoma, and Texas. Acreage has been declining (table 1), and average national yields are typically 50 to 70 bu/ac with lower yields in the southern Plains relative to the central Plains (USDA NASS). Grain sorghum is an efficient water user and is drought tolerant, particularly with respect to other agricultural crops and is often produced in dryer areas.                      Grain sorghum is typically planted in rotation with either a fallow period or with soybeans or other small grains, mostly wheat (KSU, 1998). No-till planting is best suited to well-drained soils with reduced-till methods more suitable for wetter soils (KSU, 1998). No-till and reduced till methods are used on 14% and 18% of the acres respectively with conventional till methods used on the remaining acres (CTIC, 2000).    Seeding rates are usually between 30,000 and 100,000 plants/ac depending on row spacing used, moisture and temperature conditions, and likely germination rate of the seed. Seeds are planted at 1 to 2 inch depths depending on soil type. Grain sorghum is generally planted in May or June with planting timed so that flowering occurs prior to the hottest, driest part of the summer.   Fertilizer requirements depend on soil conditions and expected yields.  Recommended nitrogen, phosphorous, and potassium rates are 0.8 to 2 lbs of elemental N/acre for every 100 lbs/ac expected grain yield, 0 to 70 lbs P2O5/ac, and 0 to 100 lbs K2O/ac. Zinc, iron, and sulfur may also be needed in small quantities in some cases (KSU, 1998; Stichler, 1997; Endres, 2000). Grain sorghum is susceptible to a number of fungal, bacteria, and viral diseases although most do not typically cause serious losses. Greenbugs and chinch bugs are important insect pests.   Harvest typically occurs 1 to 2 weeks after a killing frost (late September to October) using small grain combines. The grain is physiologically mature at 25 to 35% moisture, but needs to be below 20% moisture to harvest. Long term storage usually requires that the moisture content be below 14%. Wet-grain storage sometimes occurs in either sealed, oxygen-free systems or in open unsealed bunker or trench silos (KSU, 1998).   Typical cash production costs ($1995) range from $98 to $120/ac and total economic costs range from $179 to $189/ac (USDA-ERS).   Grain sorghum is produced primarily as cattle feed and is also used in bird seed. However, about 15% of the crop is currently used to produce ethanol or other bioproducts. The process used to produce ethanol from grain sorghum is the same as the dry grind process used for corn grain and similarly, results in the production of distiller’s dried grains that are used for livestock feed (National Sorghum Producers).    Grain sorghum yields are expected to increase slightly in the coming years. The USDA projects average national sorghum grain yields of 69.0 bu/ac and 6.0 million harvested acres by 2015 (USDA OCE).  FAPRI projects average national sorghum grain yields of 67.2 bu/ac and 5.02 million harvested acres by 2015 (FAPRI, 2006). A workshop of crop experts (English, 1997) projected that under the mostly likely scenario, average national sorghum grain yields of 89 and 102 bu/ac could be achieved by 2030 and 2050 respectively (compared to 1990-1992 yields of 65 bushels/acre) resulting from genetic, management, and equipment improvements.