Species Overview

Native to: Tropical Americas

Tropical nutrush was first detected on the landscape around 2007. It wasn’t until 2015, after it began forming dense stands in the understory of cypress and hardwood swamps, that it was positively identified. This species is currently only documented and vouchered in Polk, Orange, Osceola, and Palm Beach counties. Populations have been documented on several lakes within the Kissimmee Chain of Lakes. Because it is not widespread, early detection and rapid response to observations is a priority. If you see this plant in cultivation or in the wild, please contact the Florida Fish and Wildlife Conservation Commission at 850-617-9430.

Species Characteristics

Family: Cyperaceae

Habit: wetland sedge up to 1.25 m tall with triangular stems and 3-ranked leaves.

Leaves: blades are linear, 5 - 20 cm long and 0.5 - 0.9 cm wide, with a scabrous margin. The leaf blade is decurrent at the base, with the sheath extending wing-like down the stem to the collar. The contraligule (flap of tissue at the top of the sheath opposite the leaf blade) is lanceolate.

Achenes: unprotected (lacking surrounding bracts) which is diagnostic of this species in Florida. The hypogynium (located at the base of the achene) is cup-shaped with a ciliate margin.

Distribution in Florida: Polk, Orange, Osceola, and Palm Beach counties.

Impacts

Seeds of this plant are likely spread by wildlife and are small enough to be embedded in the tread of field shoes. Decontamination of clothing, footwear and equipment is crucial to avoid spreading this species. It can also produce new stems through rhizomes. Alters the composition and structure of native wetland communities.

Decontaminate of clothing, footwear and equipment after working or recreating in infested areas. Report suspected observations to FWC immediately.

More research needed.

None known.

a 2% foliar application of glyphosate has been most effective in the field in Central Florida, but more research is needed. It is important to consult an expert for assistance in developing the most effective and integrated approach to management.