Schoenoplectus pungens (Common Three Square)

A confirmed brackish-water specialist with real ethnobotanical significance, common three-square has been used traditionally by Indigenous communities for basketweaving, matting, and thatch, while its culm-boring larvae host three specifically named Crambid moth species.

Species Overview

Schoenoplectus pungens, commonly called common three-square, is a perennial sedge native to wetlands, marshes, and shorelines throughout North America, typically growing 1.5 to 4 feet tall. Its sharply three-angled, stout culms give the species its common name, with brownish spikelets appearing in small lateral clusters during summer.

Application

• Brackish marsh and estuarine restoration - tolerates fresh to brackish water
• Erosion control and stormwater management
• Larval host habitat for three named Crambid moth species
• Habitat creation projects - nesting and food value for wetland birds

Growing Conditions / Specification Data

• Light: Full Sun
• Soil/Moisture Tolerance: Wet to inundated soils; tolerates brackish water conditions
• Plant Type: Graminoid
• Mature Height: 2-4 ft.
• Fall Color: Insignificant/None
• Wetland Indicator Status: NI (No Indicator) - see flags
• Native Range: Northeast/Mid-Atlantic (full list)
• Pollinator Value: None significant - wind-pollinated wetland sedge/bulrush, no meaningful nectar or pollen resource.
• Hydrology: Moist-Wet
• Root Depth: Shallow (Under 12 in.)
• Salinity Tolerance: Moderate
• Growth Rate: Moderate
• Drought Tolerance: Low
• Deer Resistance: Yes (Rarely Damaged)
• Flood Tolerance: High - Dominates the middle marsh zone of tidal riverbank communities between low and high tide, alongside pickerelweed, arrow-arum, and spatterdock.
• Shade Tolerance: Intolerant
• Growth Habit: Spreading - rhizomatous
• USDA Hardiness Zones: 3-9

Planting Guidance

• Historically used by Indigenous communities for basketweaving, matting, bedding, and thatch (also known as "basket grass"); fleshy rootstock and rhizomes were historically eaten. Spreads by rhizome to form recoverable colonies after damage.