Overview
Dulichium arundinaceum is a rhizomatous perennial sedge in the sedge family that grows 12–36 inches (30–90 cm) tall in shallow water and saturated soil. Unlike most sedges, it has hollow, round, jointed stems that resemble small bamboo. The leaves are flat, 1.5–5 inches (4–13 cm) long, and arranged in three vertical ranks up the stem, which gives the plant its three-way appearance and common name. From July to October flattened spikelets 0.3–0.8 inch (8–20 mm) long emerge from the upper leaf axils in two rows, ripening from green to straw-brown. The plant spreads by creeping rhizomes to form colonies along pond and lake margins, in bogs, marshes, and ditches. It grows in standing water up to about 12 inches (30 cm) deep and in soil that stays wet through the season. Stems and foliage die back in autumn and new shoots rise from the rhizomes in spring. It does not tolerate dry soil or prolonged drawdown, and it can spread aggressively in constructed ponds and water gardens. The seeds and shoots are eaten by waterfowl and marsh birds.
Native Range
Native across much of North America, from Canada south through the eastern and western United States, in wetlands at the edges of ponds, lakes, bogs, and slow streams. It grows in acidic to neutral, permanently moist or shallowly flooded soils.Suggested Uses
Dulichium arundinaceum is used at pond and lake margins, in bog gardens, constructed wetlands, and rain gardens for shoreline stabilization. Its seeds and shoots feed waterfowl and marsh birds, and the colony shelters wetland wildlife. It suits naturalized water features where its spreading habit can be accommodated.How to Identify
Appearance
Size & Dimensions
Height1' - 3'
Width/Spread1' - 2'
Bloom Information
Detailed Descriptions
Flower Description
green to straw-brownFoliage Description
greenGrowing Conditions
Sun Requirements
Requires 4-12 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
Care & Maintenance
Care Guide
Dulichium arundinaceum grows in full sun to part shade in standing water up to 12 inches (30 cm) deep or in soil that stays saturated through the season. It tolerates acidic, low-nutrient water and is used at the margins of ponds and rain gardens. The plant spreads by rhizomes and can form dense colonies, so it is often confined to containers in small water features. It needs consistently wet conditions and declines if the soil dries out. New growth rises from the rhizomes each spring after the previous year''s stems die back. It tolerates a range of water chemistry but grows densest in acidic wetlands.Pruning
Dulichium arundinaceum needs little pruning. Dead stems can be cut back in late winter before new growth emerges. Rhizomes can be divided in spring to control spread or to propagate new clumps.Container Growing
✓ Suitable for container growing
Minimum container size: 3 gallons