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Cogongrass

Imperata cylindrica (im-peh-RAH-tah si-LIN-dri-ka)

Family: Poaceae Non-native Herbaceous (3-15 ft)

Japanese Bloodgrass is an extremely aggressive weed that is considered invasive in North Carolina. It probably originated in Africa and Asia and was accidentally introduced in LA in 1912 and then intentionally to FL in the 1930s. It was used as packing material in the past and then for erosion control and animal forage. It quickly spread and invaded areas such as pastures, fallow fields, forests, and highway and powerline rights-of-way. It spreads rapidly through scaly rhizomes and quickly becomes difficult to manage. It is also highly flammable and increases the risk of wildfires. The plant regenerates after a fire and quickly takes over an area. The green leaves grow up to 30 inches tall and 1/2 to 3/4 inches wide. They are finely toothed and embedded with sharp silica crystals. The rhizomes are extensive and can penetrate 2-4 feet deep. It rarely flowers in its northern range. In more tropical areas it freely flowers with 16-inch panicle inflorescences. There is a cultivar called 'Red Baron' that is supposedly sterile but it has been known to break sterility and revert back to the green form. It is not wise to plant this cultivar either. This grass is considered the seventh worst weed in the world and listed as a federal noxious weed by USDA Animal and Plant Health Inspection Service - Plant Protection and Quarantine. See alternative grasses to grow to the left. Fire Risk: This plant has an extreme flammability rating and should not be planted within the defensible space of your home. Select plants with a low flammability rating for the sites nearest your home. Insects, Diseases, and Other Plant Problems: No serious insect or disease problems. This plant is invasive.

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 41 attributes.

How it fits the guild

Guild layer 4 - Herbaceous (3-15 ft)
See companions & conflicts ↓

Companions & Conflicts

Curated pairwise relationships between this plant and others in the library — who feeds whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.

No curated interactions recorded for this species yet.

Also noted by NC State

Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.

Fills a similar niche Imperata cylindrica 'Rubra' Phyllostachys aureosulcata Pyrus calleryana

Full plant profile

Growing Conditions
Plant type
Weed
Life cycle
Perennial
USDA zones
5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b
Light
Full sun (6 or more hours of direct sunlight a day) | Partial Shade (Direct sunlight only part of the day, 2-6 hours)
Soil texture
Clay; Loam (Silt); Sand
Soil drainage
Good Drainage | Moist | Occasionally Dry
Available space
12 inches-3 feet; 3 feet-6 feet
NC region
Coastal; Mountains; Piedmont
Mature size
Height: 2 ft. 0 in. - 4 ft. 0 in. | Width: 2 ft. 0 in. - 4 ft. 0 in.
Growth rate
Rapid
Maintenance
High
Canopy layer
4 - Herbaceous (3-15 ft)
Form & Appearance
Habit / form
Clumping; Erect; Spreading
Texture
Medium
Leaf color
Gold/Yellow; Green
Leaf shape
Linear
Leaf margin
Serrate
Leaf size
> 6 inches long, < 1 inch wide
Hairs present
No
Leaf detail
Basal stiff leaf blades are yellow-green 3/4" wide and up to 30 inches long with tiny serrated margins, light green or white midribs that are of center and pointed tips. Margins are finely toothed and are embedded with sharp silica crystals. Upper surface has a few hairs near the base, undersides are smooth.
Flower form
Panicle; Raceme
Flower detail
Infrequently flowers in northern parts of its growing region but flowers freely in tropical areas. 16" long panicle that branch out into racemes.
Bloom time
Summer
Fruit detail
fuzzy, white, and plume-like seed heads
Wildlife & Ecology
Native status
Non-native
Origin
Africa, Europe, Asia
Food & Medicine

Uses (ethnobotany)

It has been used in traditional medicines.

Landscape Use
Garden tags
#aggressive #fast growing #invasive #high maintenance #black walnut toxicity tolerant #air pollution tolerant #self-seeding #drought tolerant #Noxious Weed (Federal list) #fire high flammability #fire extreme flammability #weedy #poor soil tolerant
Problems & Resistance
Problems
Invasive Species; Weedy
Resistant to
Black Walnut; Drought; Pollution; Poor Soil
Propagation
Seed
Fire risk
extreme flammability

Planted at Hunnicutt

Nobody’s planted this one yet.