Serrated tussock grass, Nassella trichotoma, is a perennial grass that grows up to a height of 11.8 ft. (60 cm) and forms tussocks. It reaches a maximum of 9.8 in. (25 cm) across the base and has a deep fibrous root system. It can live for over 20 years.

Foliage

The leaves are thin and tightly rolled, about 0.02 in. (0.5 mm) in diameter. The leaf blade has serrations along the margin. The white ligule is about 0.04 in. (1 mm) long.

Flowers

Inflorescence is open and branching. Florets have a long awn about 1 in. (2.5 cm) long.

Fruit

Fruit is a caryopsis (grain) which is typical of grasses. A mature plant can produce over 140,000 seeds per year. Lightweight seed can be spread by the wind.

Ecological Threat

N. trichotoma is of low nutritional quality and it can tolerate a wide range of habitats. N. trichotoma can infest grazing lands, dominating large areas and making it inadequate for supporting livestock. It can also invade native grasslands because it produces such a large number of seeds.

Citations

Rawlins, K.A., R.L. Winston, C.T. Bargeron, D.J. Moorhead, and R. Carroll. 2018. New Invaders of the Southeast. USDA Forest Service, Forest Health Assessment and Applied Sciences Team, Morgantown, West Virginia. FHTET-2017-05. Retrieved from http://bugwoodcloud.org/resource/pdf/FHTET-2017-05_New%20Invaders_SE.pdf
 

Resources

• Federal Noxious Weed Disseminules of the U.S. - USDA-APHIS

Selected Images

Maps

Invasive Listing Sources

• California Invasive Plant Council
• Federal Noxious Weeds
• Florida Noxious Weeds
• Hawaii Noxious Weeds
• Maryland Code and Regulations Noxious Weed & Seed Law
• Massachusetts Noxious Weeds
• Massachusetts Prohibited Plant List
• Michigan Noxious Weeds
• New Invaders of the Southeast
• Ohio Noxious Weeds
• South Carolina Plant Pest List
• Texas Noxious Weeds
• USDA APHIS Regulated Pest List

References