John D. Byrd, Bugwood.org,
Mississippi State University
Family: Poaceae (Grass Family)
Synonym(s): Panicum gouinii
Duration: Perennial
Habit: Grass/Grasslike
Listed by:
Invasive Plant Atlas of the US: 1
Federal Noxious Weed: 0
TDA Noxious Weed: 1
TPWD Prohibited Exotic Species: 1
Description: Torpedograss is a perennial grass that can reach up to 3 ft. (1 m) tall. Plants have long, creeping rhizomes with sharp-pointed (torpedo-like) tips. Leaves are linear, flat or folded, 10 in. (26 cm) long, 0.3 in. (5.3 mm) wide with a whitish, waxy covering. Leaf sheaths can be smooth or hairy and the ligule is membranous with short hairs. Flowering occurs nearly year round. Florets develop in branched, open inflorescences that are 2.8-7.1 in. (7-18 cm) long and are yellow or straw in coloration.
History: Torpedograss was first documented in the US in 1876 in Alabama but it is believed to have been introduced to the United States earlier in Louisiana. This type of grass was used for agriculture because cattle did not trample it as easily due to its structure.
Biology & Spread: Propagation occurs primarily vegetatively by rhizome growth but seeds may also be dispersed by human activity or water. Torpedo grass flowers nearly year-round, but it is variable in its seed abundance and viability.
Ecological Threat: Torpedograss is highly resilient and can survive during extreme drought conditions but prefers moist soil. Once established this grass is very difficult to eradicate. It quickly forms monocultures that displace native vegetation, particularly in or near shallow waters
US Habitat: This species can occur in a wide variety of habitats. Plants are usually found in damp soils of riparian zones, but can also be found in pastures and on sand dunes. Plants are salt
Distribution
US Nativity: Introduced to U.S.
Native Origin: Africa and Eurasia
US States: AL, CA, FL, HI, LA, MS, NC, SC, TX
Resembles/Alternatives:
Management: Preventative: Control can be accomplished to some degree by preventing the spread and fragmentation of rhizomes. This can be very difficult because if even a tiny fragment of rhizome remains, it will reestablish itself. Control of infestations near waterways will prevent long-range spread via water and this should be a priority.
Cultural: Weeds such as torpedograss generally invade open or disturbed areas following a burn, clearing mowing, etc., so these areas are particularly vulnerable to invasion. Therefore, a healthy ecosystem with high species diversity may help to deter infestation.
Mechanical and Biological: Currently, there are no available biological control agents for torpedograss. There are limited agents being researched, and Dr. Charudattan at the University of Florida has been evaluating a species of fungus. Torpedo grass is very palatable for cows and goats, and grazing may be integrated in an overall management scheme. If mowing or tillage is used, care must be taken to prevent transport of rhizome or stolon fragments.
Chemical: Herbicide can be effective for controlling torpedograss in some situations. Glyphosate has proven effective for treating torpedograss above the water line but ineffective on plants growing in the water.
USE PESTICIDES WISELY: ALWAYS READ THE ENTIRE PESTICIDE LABEL CAREFULLY, FOLLOW ALL MIXING AND APPLICATION INSTRUCTIONS AND WEAR ALL RECOMMENDED PERSONAL PROTECTIVE GEAR AND CLOTHING. CONTACT YOUR STATE DEPARTMENT OF AGRICULTURE FOR ANY ADDITIONAL PESTICIDE USE REQUIREMENTS, RESTRICTIONS OR RECOMMENDATIONS. MENTION OF PESTICIDE PRODUCTS ON THIS WEB SITE DOES NOT CONSTITUTE ENDORSEMENT OF ANY MATERIAL.
Listing Source
Texas Department ofAgriculture Noxious Plant List
Texas Parks and Wildlife Department Prohibited Exotic Species
Invaders Program
Federal Noxious Weed
Union of Concerned Scientists
United States Forest Service Southern Research Station
Text References
Center for Aquatic and Invasive Plants. 2009. Panicum repens: Torpedo Grass. University of Florida, IFAS.
Florida Exotic Pest and Plant Council. Panicum repens: torpedo grass. Accessed February 2009: http://www.fleppc.org/ID_book/Panicum%20repens.pdf.
Data Source
Miller, J.H. 2003. Nonnative invasive plants of southern forests: a field guide for identification and control. Gen. Tech. Rep. SRS-62. Asheville, NC: U.S. Department of Agriculture, Forest Service, Southern Research Station. 93 pp (USDA SRS).
Bugwood Network. Bugwood.org
Last Updated: 2024-02-09 by ARMO, TISI