Tridens flavus (Purpletop)

A confirmed road-salt tolerant grass genuinely at home in the toughest roadside ditches, purpletop is a documented larval host for the Common Wood Nymph, Crossline Skipper, Little Glassywing, and Broad-winged Skipper - a rich roster of butterflies for a species often overlooked as a simple old-field grass.

Species Overview

Tridens flavus, commonly called purpletop or grease grass, is a large, warm-season perennial bunchgrass native to fields, roadsides, and open woodlands across the eastern United States, growing 2 to 4 feet tall. Distinctive light purple, feathery, oily-seeded flower clusters bloom from mid-summer into early fall, giving the species its common name and persisting into November.

Application

• Salt-tolerant roadside ditch and disturbed-site restoration
• Larval host habitat for the Common Wood Nymph, Crossline Skipper, Little Glassywing, and Broad-winged Skipper
• Erosion control - deep, fibrous, colonizing root system
• Naturalized meadow and prairie plantings - striking purple fall display

Growing Conditions / Specification Data

• Light: Full Sun to Part Shade
• Soil/Moisture Tolerance: Dry to average, well-drained soils; sandy to clay
• Drought Tolerance: High
• Flood Tolerance: Low - A dry-mesic old-field grass, consistent with this species' already-confirmed habitat profile from earlier work.
• Plant Type: Graminoid
• Mature Height: 2-4 ft.
• Fall Color: Purple - distinctive purplish seed heads
• Wetland Indicator Status: NI (No Indicator) - see flags
• Native Range: Northeast/Mid-Atlantic (full list)
• Hydrology: Dry-Mesic
• Root Depth: Moderate (12-24 in.)
• Salinity Tolerance: Low
• Growth Rate: Moderate
• Deer Resistance: Yes (Rarely Damaged)
• Shade Tolerance: Intolerant
• Growth Habit: Clumping/Mounding
• USDA Hardiness Zones: 5-9
• Pollinator Value: Larval host, supports butterflies

Planting Guidance

• Seeds are oily, giving rise to the alternate common name "grease grass"; seed heads are high in fat and prized by birds and small mammals through winter. A great colonizing grass with deep, fibrous roots that help control erosion on disturbed sites.

Please allow 3 business days for all seed orders.