Mississippi Forages  Connecting the Livestock Industry and Producers to Success!
Sorghum-sundagrass (Sorghum bicolor) Physical Characteristics: Seed: Round seed with dark undercoat (bluish white). Leaf: Vernation: rolled in the bud. Sheath: smooth and open. Blade: similar to corn leaf but shorther and not wide, smooth and boat shapped. Collar:  medium to broad. Auricle: absent. Ligule: long with fringe of hairs. Root: Fibrous root system. Flower: Open panicle with red flummed seeds. with oranged to reddish seeds at the bottom. Managment: Soil Adaptation:  Best adapted to well-drained soils and can tolerate somewhat poorly darained soils.  Good drought tolerant but does not tolerate low pH soils. Planting Dates: May 1 to July 15. Seeding Rate: 20 to 25 lb/ac drilled and 30 to 35 lb/ac broadcast (13,000 to 24,000 seeds per pound).  Planting Depth: ½ to 1 inch. Fertilization: 40 to 50 lb N/ac at establishment. Apply 40 to 60 lb N/ac after each cutting or grazing period. Lime, P and K should be applied based on soil test recommendations. Production Season: Yield are impacted by planting dates. Approximately 90% of production occurs in June, July and August.  The first grazing can occur within 45 to 60 days after planting depending on environmental conditions. Expected Yields: Yields will depend on planting date, fertilization, and growing conditions.  Yield can range from 3,000 to 8,000 lbs of dry matter forage per acre. Utilization: Grazing, silage, and hay.  If grazing, a rotation in recommended and stagger planting to avoid maturity issues.  Grazing sorghum- sudangrass should begin when the plants are between 18 to 30 inches tall and grazed down to 8 inches within 10 days.  Do not graze after a killing frost until the plants turn completely brown (7 days). If the plants are frost damaged, wait until the regrowth is at least 18 inches high before grazing again.  Silage should be harvested when the plants are 36 to 48 inches tall or in the boot to early head stage.  If used for hay, a mower contidioner is recommened due to thick stems.  Harvesting for hay is recommended before head emergence or when the plants reach 48 inches in height. Pests: Rust, grasshopers, sugarcane aphid. Toxicity: Prussic acid (hydrocyanic acid HCN), nitrates.