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Fothergilla gardenii Witch Alder
Fothergilla gardenii (Witch Alder). Photo © Mary Free
You are here: Home / Plants / Tried and True Native Plant Selections for the Mid-Atlantic / Grasses & Sedges / Chasmanthium latifolium
(River or Wild Oats, Northern Sea Oats)

Chasmanthium latifolium
(River or Wild Oats, Northern Sea Oats)

Chasmanthium latifolium (River or Wild Oats, Northern Sea Oats) winter foliage in January.
Chasmanthium latifolium (River or Wild Oats, Northern Sea Oats) in winter landscape.
Chasmanthium latifolium (River or Wild Oats, Northern Sea Oats) in May.
A culm of native Chasmanthium latifolium (river oats) showing leaf blade and open sheath.
Glabrous culms (nodes and internodes), blades, and sheaths of Chasmanthium latifolium (river oats)
Chasmanthium latifolium (River or Wild Oats, Northern Sea Oats) seed heads in July. 2015-07-25, National Arboretum.
Close up of Chasmanthium latifolium (River or Wild Oats, Northern Sea Oats) seed heads in August. 2017-08-21, Glencarlyn Library Community Garden.
Chasmanthium latifolium (River or Wild Oats, Northern Sea Oats) in container in September. 2017-09-30, Meadowlark Botanical Gardens.
Chasmanthium latifolium (River or Wild Oats, Northern Sea Oats) in October landscape. 2017-10-17, private garden, Arlington, Virginia.

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This beautiful, tall woodland grass* grows in upright clumps and produces fresh green, bamboo-like leaves that are held perpendicular at intervals on smooth, round culms (stems). Panicles stand well above the foliage with drooping, eye-catching oat-like seed heads that rustle and shimmer in the breeze. Grass / Sedge Clumps, Maturing Seed Heads, in Winter Height: 2–5 feet Spread: 2–3 feet Bloom Color: Green then tan Characteristics Tall perennial grass in upright clumps Alternate, arching, glabrous, bright green leaves Culms terminate in nodding panicles of flat, oat-like spikelets maturing from green to pink to tan/copper Leaves turn yellow-gold to copper in fall Self-seeds; can spread vigorously Attributes Tolerates shade, salt, and Black Walnut No serious pests or diseases; deer rarely damage Winter interest Use in cut and dried arrangements Larval host for Common Roadside Skipper Growing and Maintenance Tips Excellent Replacement for Soil Requirements: Average, well-drained Cortaderia seelloana - Pampas Grass Light Requirements: Sun, Partial Shade Melilotus officinalis - Sweetclover Water Requirements: Dry, Moist, Wet Sunnier sites produce brighter fall color but require more water Allow seed heads to ripen and stand through fall and winter; cut to ground in early spring Use in borders, in rain gardens, and to control erosion in shady areas; looks best planted in groups, lovely on slopes *It is native to DC, historical in the DE Piedmont and found in very few scattered pockets in PA. In VA, it is locally common throughout the mountains (low elevations), Piedmont and inner Coastal Plain and rare in the outer Coastal Plain. It is native to NoVA, except to Prince William County. Hardiness: USDA Zones 3–8 developed by Master Gardeners of Northern Virginia, serving Arlington and Alexandria Images by Mary Free and Elaine Mills (bottom left), Glencarlyn Garden

Tried and True Native Plant Selections 
for the Mid-Atlantic

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Chasmanthium latifolium (River or Wild Oats, Northern Sea Oats)

This beautiful, tall woodland grass* grows in upright clumps and produces fresh green, bamboo-like leaves that are held perpendicular at intervals on smooth, round culms (stems). Panicles stand well above the foliage with drooping, eye-catching, oat-like seed heads that rustle and shimmer in the breeze.

*It is native to DC, historical in the DE Piedmont and found in very few scattered pockets in PA. In VA, it is locally common throughout the mountains (low elevations), Piedmont and inner Coastal Plain and rare in the outer Coastal Plain. It is native to NoVA, except to Prince William County.

Learn more about other Mid-Atlantic plants: 
Tried and True Native Plant Fact Sheets