Paspalum urvillei

vasey grass

Nonnative to Florida

Species Overview

Native to: South America

Introduced to the U.S. as a pasture grass in the late 1800s, the earliest Florida specimen was vouchered in 1943. This medium-large grass is now commonly found growing in moist, open, disturbed sites throughout the state. 

Species Characteristics

Family: Poaceae

Habit: Perennial bunch grass with tufted stems and growing to 7 feet tall

Leaves: Long and narrow with entire margins, indented midrib, and pointed tips. Leaf margin are crinkled. Leaf blades grow up to 15 inches long and half an inch wide. Leaves are mostly hairless, except some long hairs near their narrow bases.

Flowers: Conspicuous, to 1 ft. long, 4-30 ascending overlapping branches, branches to 5 in. long. Spikelets paired, in four rows, elliptic, margins with long hairs.

Seeds: Alternating spikelets forming silky hairs around the seeds. Seeds are produced along the entire length of the seedhead branch.

Distribution in Florida: Statewide

Impacts

Likely spread to new areas via mowing and tilling equipment and fill dirt. Seeds can also be dispersed by wind and water. Widely recognized as an agricultural weed, it can reduce yields by outcompeting crop plants, introducing pests or pathogens and through allelopathic activity. It can also displace native plants especially in disturbed areas.

Control Methods

Preventive Measures

Clean all equipment and clothing that has been exposed to infested areas. Ensure any equipment, mulch or soil/fill introduced to an area is not contaminated.

Cultural/Physical

Small infestations may be dug out, taking care to remove all root material.

Mechanical

Mowing and tilling can make the problem worse by scattering and burying the seeds.

Biological

None known.

Chemical

Spot spraying with 1% Glyphosate solution (1.2 oz/gal) can be effective. Care should be taken to avoid contact with desirable grasses. Consult your local UF IFAS Extension Office for management recommendations.

Learn more about this species

UF IFAS Assessment of Non-Native Plants in Florida’s Natural Areas

Identification and Control of Johnsongrass, Vaseygrass, and Guinea grass in Pastures

Atlas of Florida Plants

EDDMapS

USDA Plant Database

Invasive Species Compendium