Panicum virgatum L., switchgrass 
DESCRIPTION 
Warm-season, rhizomatous perennial. 
Height: 3 to 6 feet. 
Leaf blade: Flat; 1/2 inch wide; sometimes 30 inches long. 
Leaf sheath: Rounded; smooth; as long as or longer than in- 
ternodes. 
Ligule: Dense ring of hair; 1/8 inch long. 
Seedhead: Open panicle about 10 inches long. 
GROWTH CHARACTERISTICS 
Makes major growth from March through September. Growing 
points are 4 to 5 inches above ground during latter part of growing 
season. Seedheads form during late August and September. Rhi- 
zomes grow actively during January, February, March, and April. 
Withstands temperatures of -25° to -30° F. without apparent 
damage. Produces 3 to 4 tons of forage and 100 to 150 pounds of 
seed per acre in pure stands. But the number of pure live seed per 
pound is low. 
DISTRIBUTION 
Rocky Mountains, south into Arizona and northern Mexico, east 
to Atlantic coast. 
SITE ADAPTATION 
Grows equally well on the highly calcareous soils of central 
Texas and the wet, acid soils of south Florida. Also grows well in 
brackish marshes. 
USE AND MANAGEMENT 
Switchgrass is used primarily for livestock grazing. In some lo- 
calities, it is cut for hay. It is also used for seeding ranges and pas- 
tures. Birds eat the seed. 
This grass responds to proper grazing use and periodic defer- 
ments of at least 90 days any time of year. For maximum produc- 
tion of good-quality hay, meadows should not be grazed in early 
spring and hay crops should be harvested when seedheads are well 
formed. Meadows can be grazed moderately in late fall. 
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