Plant DetailShow Menu

Chasmanthium latifolium

Previously known as:

  • Uniola latifolia
Phonetic Spelling
chas-MAN-thee-um lat-ih-FOH-lee-um
Description

River Oats is a native, clump-forming, upright grass in the Poaceae (grass) family.  This easy to grow ornamental grass reaches a height between 2 to 5 feet and width of 1 to 2 feet.

The distinctive flat nodding seed heads that resemble oats emerge green in spring, turn tan in summer and then purplish in fall. They sway gracefully in the slightest breeze. The bamboo-like leaves often turn yellow-gold in fall if given enough sun.  This plant is a larval host plant for butterflies as well as a food source for small mammals and birds.

It is easily grown in moist to wet well-drained soils in part sun to part shade. It is fairly tolerant of shade, especially for an ornamental grass.   

Use in naturalized areas, along streams or edges of water gardens.  Watch its placement especially in smaller gardens as may spread aggressively by rhizomes and seeds.

This plant was selected as the 1994 NC Wildflower of the Year, a program managed by the North Carolina Botanical Garden with some financial support from the Garden Club of North Carolina.

Insects, Diseases, and Other Plant Problems:  It can be a bit weedy as it self seeds easily.

See this plant in the following landscapes:
Dry Rock Stream Garden Native Woodland Garden, Durham
Cultivars / Varieties:
Tags:
#rain garden#easy to grow#salt tolerant#shade garden#erosion control#pond margins#NC native#spreading#deer resistant#skipper butterflies#shimmer#pollinator plant#wind pollinated#native ornamental grass#larval host plant#food source summer#showy seedheads#food source fall#food source herbage#Coastal FAC#wet soils tolerant#bird friendly#food source hard mast fruit#mammals#butterfly friendly#Piedmont Mountains FACU#partial shade tolerant#Audubon#northern pearly-eye butterfly#NC Wildflower of the Year#weed#stormwater garden#wildlife friendly
 
Cultivars / Varieties:
Tags:
#rain garden#easy to grow#salt tolerant#shade garden#erosion control#pond margins#NC native#spreading#deer resistant#skipper butterflies#shimmer#pollinator plant#wind pollinated#native ornamental grass#larval host plant#food source summer#showy seedheads#food source fall#food source herbage#Coastal FAC#wet soils tolerant#bird friendly#food source hard mast fruit#mammals#butterfly friendly#Piedmont Mountains FACU#partial shade tolerant#Audubon#northern pearly-eye butterfly#NC Wildflower of the Year#weed#stormwater garden#wildlife friendly
  • Attributes:
    Genus:
    Chasmanthium
    Species:
    latifolium
    Family:
    Poaceae
    Life Cycle:
    Perennial
    Recommended Propagation Strategy:
    Division
    Seed
    Country Or Region Of Origin:
    Central Canada, Central & E. U.S.A. to NE. Mexico
    Distribution:
    AL , AR , AZ , DC , DE , FL , GA , IA , IL , IN , KS , KY , LA , MD , MI , MO , MS , NC , NJ , NM , OH , OK , PA , SC , TN , TX , VA , WI , WV
    Wildlife Value:
    This is a larval host plant for Northern Pearly-Eye (Lethe anthedon) caterpillars. You may see two broods from May-September in the south or one brood from June-August in the north. Highly resistant to deer. Also a larval host plant to several skipper butterflies. Small mammals and birds are attracted to the seeds.
    Play Value:
    Shade
    Wildlife Cover/Habitat
    Wildlife Food Source
    Wildlife Larval Host
    Wind Shimmer
    Dimensions:
    Height: 2 ft. 0 in. - 5 ft. 0 in.
    Width: 1 ft. 0 in. - 2 ft. 6 in.
  • Whole Plant Traits:
    Plant Type:
    Native Plant
    Ornamental Grasses and Sedges
    Woody Plant Leaf Characteristics:
    Deciduous
    Habit/Form:
    Clumping
    Erect
    Growth Rate:
    Medium
    Maintenance:
    Medium
    Texture:
    Coarse
  • Cultural Conditions:
    Light:
    Dappled Sunlight (Shade through upper canopy all day)
    Partial Shade (Direct sunlight only part of the day, 2-6 hours)
    Soil Texture:
    Clay
    Loam (Silt)
    Sand
    Soil Drainage:
    Moist
    Occasionally Wet
    Available Space To Plant:
    12 inches-3 feet
    NC Region:
    Coastal
    Mountains
    Piedmont
    USDA Plant Hardiness Zone:
    5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b
  • Fruit:
    Fruit Color:
    Brown/Copper
    Cream/Tan
    Gray/Silver
    Purple/Lavender
    Fruit Value To Gardener:
    Long-lasting
    Showy
    Display/Harvest Time:
    Fall
    Summer
    Fruit Type:
    Caryopsis
    Fruit Description:
    Seed heads are green to tan then purplish bronze from July to November.
  • Flowers:
    Flower Color:
    Brown/Copper
    Green
    Purple/Lavender
    Flower Inflorescence:
    Panicle
    Spike
    Flower Value To Gardener:
    Good Dried
    Long-lasting
    Showy
    Flower Bloom Time:
    Fall
    Summer
    Flower Size:
    1-3 inches
    Flower Description:
    The inflorescence is an open panicle with branches nodding or drooping. It is initially green, turning brown at maturity. The individual spikelets are up to 1-1/2 inches long and over 1/2 inch wide, with typically 6 to 17 florets. Flowers bloom from June to October and are wind pollinated.
  • Leaves:
    Woody Plant Leaf Characteristics:
    Deciduous
    Leaf Color:
    Green
    Leaf Value To Gardener:
    Long-lasting
    Showy
    Deciduous Leaf Fall Color:
    Brown/Copper
    Gold/Yellow
    Leaf Type:
    Simple
    Leaf Arrangement:
    Alternate
    Leaf Shape:
    Lanceolate
    Linear
    Leaf Margin:
    Entire
    Hairs Present:
    No
    Leaf Length:
    > 6 inches
    Leaf Width:
    < 1 inch
    Leaf Description:
    5-9 inch long and 1-inch wide flat green leaf blades are upright to slightly arching, turn a yellow-coppery color in fall and brown in winter.
  • Stem:
    Stem Color:
    Green
    Stem Is Aromatic:
    No
    Stem Cross Section:
    Round
    Stem Surface:
    Smooth (glabrous)
    Stem Description:
    Green and smooth
  • Landscape:
    Landscape Location:
    Container
    Naturalized Area
    Pond
    Riparian
    Woodland
    Landscape Theme:
    Butterfly Garden
    Cottage Garden
    Native Garden
    Pollinator Garden
    Shade Garden
    Water Garden
    Winter Garden
    Design Feature:
    Accent
    Border
    Mass Planting
    Attracts:
    Butterflies
    Pollinators
    Small Mammals
    Songbirds
    Resistance To Challenges:
    Black Walnut
    Deer
    Drought
    Erosion
    Salt
    Wet Soil
    Problems:
    Weedy