Bothriochloa ischaemum
king ranch bluestem
Overview
Bothriochloa ischaemum is a warm-season perennial bunchgrass in the family Poaceae, forming dense tufts 1-3 feet (30-90 cm) tall from a knotty crown. The slender stems carry narrow blue-green to gray-green leaf blades 2-6 inches (5-15 cm) long that fold or curl in dry weather. In summer and fall each stem ends in several finger-like racemes, 1-3 inches (2.5-8 cm) long, that radiate from a single point and turn silvery to purplish as the seeds mature, covered in soft white hairs. Native to the grasslands of southern Europe and Asia, it was introduced to North America for forage and erosion control and has since naturalized widely across the southern United States. On many sites it forms near-monocultures that crowd out native grasses and lower plant diversity, and its forage value declines sharply as it matures. The grass withstands heat, drought, mowing, and grazing, regrowing quickly from its crown, which makes established stands difficult to remove. It greens up in late spring and turns straw-colored after frost.
Native Range
Native to the warm-temperate grasslands of southern Europe, the Mediterranean, and central and southern Asia. It was introduced to North America in the twentieth century for forage and soil stabilization and is now naturalized across Texas, Oklahoma, and much of the southern and southwestern United States.Suggested Uses
Planted in the past for pasture, hay, and erosion control on dry rangeland, though its low mature forage value and invasive spread have reduced its use. It persists on roadsides, reclaimed land, and overgrazed range. On many sites it is now managed as an invasive weed rather than a forage crop.How to Identify
Appearance
Size & Dimensions
Height1' - 3'
Width/Spread1' - 1'6"
Colors
Foliage Colors
Bloom Information
Flowering occurs from June through October, continuing through the warm season after summer rains. New flowering stems rise over many weeks, so seed heads at several stages often appear together. Seed set is heavy, and the grass spreads readily from wind- and animal-dispersed seed.
Detailed Descriptions
Flower Description
silvery to purplishFoliage Description
blue-green to gray-greenGrowing Conditions
Sun Requirements
Requires 6-12 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight