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Tridens spp.
Purpletop
Overview
Tridens is a genus of about fifteen warm-season grasses in the family Poaceae, native to the Americas and most strongly represented in the United States and Mexico. Most are tufted perennial bunchgrasses forming clumps of narrow leaves with airy flowering panicles held well above the foliage. The purpletop, T. flavus, is the widely seen species, a clump-former 2-5 feet (0.6-1.5 m) tall whose open, branching seed head flushes purple to bronze in late summer and is coated with a sticky, greasy film that gives the alternative name greasegrass. The genus grows in prairies, old fields, open woods, and roadsides, often on poor or disturbed ground. The narrow leaves turn yellow to bronze in autumn before the clump goes dormant for winter. Plants are wind-pollinated, with the colour and movement of the panicle being the main feature rather than any showy flower. Spread is by seed and slowly expanding clumps, and the grasses tolerate heat, drought, and poor soil once established, though they can self-seed into open ground. The genus name refers to the three small teeth at the tip of each flower scale.
Native Range
Native to the Americas, with most species in the central and eastern United States and Mexico and a few extending into South America, in prairies, open woods, old fields, and along roadsides.Suggested Uses
Grown in prairie and meadow plantings, native and wildlife gardens, and mixed borders for the airy purple seed heads and autumn colour. Used in restoration and as forage and cover on poor soils within its range.How to Identify
Appearance
Size & Dimensions
Height2' - 5'
Width/Spread1' - 2'
Bloom Information
Detailed Descriptions
Flower Description
purple to bronzeFoliage Description
green, bronze in autumnGrowing 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