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Federal Noxious Weed TDA Noxious Weed TPWD Prohibited Exotic Species 
Invasive Plant Atlas of the USNOTE:
means species is on that list.
Paspalum urvillei
Vasey grass
Synonym(s): Paspalum larranagai
Family: Poaceae (Grass Family)
Duration and Habit: Perennial Grass/Grasslike
Photographer: Chris Evans
Source: The University of Georgia, Bugwood.org
Description
Grass species are notoriously difficult to identify. Vaseygrass is a perennial grass that grows in clumps or tufts of a few to many stems growing from a short rootstock. Stems are purplish and hairy at the base but green and smooth towards the top; they are from 0.75 to 2.5 metres tall. The blades are green, vase-shaped, bristly and firm, 12 to 48 cm long (commonly 20 to 30 cm) and 3 to 15 mm wide; rarely, they can be up to 65 cm long and 2 cm wide. Each flower cluster bears six to 25 spikes. Four to thirty seedheads, grouped on spreading branches, have paired seeds lined up in 4 rows. Seeds characteristically lie on one side of the branch, are brown when mature, fringed with fine hairs, and may feel sticky.
Native Lookalikes: Currently no information available here yet, or there are no native Texas species that could be confused with Vasey grass.
Ecological Threat: It shows allelopathic activity that can impact crop systems. Crops affected in one or more ways include rice, sugarcane, maize, the fodder grass, Sorghum, oats, millet, pineapples, apples and citrus.
It is also a host of the rice stink bug, Oebalus pugnax, the Mexican rice borer, Eoreuma loftini, and the crop pathogenic bacterium, Acidovorax avenae.
Biology & Spread: As a member of the Poaceae, it is wind-pollinated. It reproduces both by seed and by rhizomes with heavy seed production (970,000 seeds/kg) and a persistent seedbank, lasting at least 9 months. The seed (fruit) is 1.8 to 2 mm long, elliptical, pale and nearly smooth.
History: Widely introduced as a forage grass. It invades and establishes in highly disturbed natural ecosystems
U.S. Habitat: Wide variety of including: disturbed areas, crop fields, forests, roadsides, wetlands, farmlands, meadows, etc.
Distribution
U.S. Nativity: Introduced to U.S.
Native Origin: South America
U.S. Present: AL, AR, CA, FL, GA, HI, KS, KY, LA, MO, MS, NC, OK, PR, SC, TN, TX, VA
Distribution in Texas: Widespread throughout the state except Panhandle and West Texas regions.
Mapping
Invaders of Texas Map: Paspalum urvillei
EDDMapS: Paspalum urvillei
USDA Plants Texas County Map: Paspalum urvillei
Invaders of Texas Observations
List All Observations of Paspalum urvillei reported by Citizen Scientists
Native Alternatives
Management
Physical/Mechanical: Continuous grazing for 2 years decreased P. urvillei cover by 15%; grazing pastures to a 15 cm stubble height increased P. urvillei density while grazing to a 30 cm stubble height decreased its density. Small populations can be cut out, making sure to remove rhizomes; slashing followed by herbicide treatment is an alternative.
Chemical: Vaseygrass is sensitive to imazapyr as well as glyphosate.
A formulation of mesotrione, terbuthylazine and S-metolachlor has been evaluated as a substitute for atrazine in the control of weeds in sugarcane fields; but a combination of trifluralin and atrazine is also effective.
Hexazinone and bromacil gave the most effective control of P. urvillei with pineapple crops.
Glyphosate controlled P. urvillei on railway rights-of-way. FAO recommends the use of 2,2-DPA (dalapon) plus paraquat, sprayed three times at 10-day intervals.
Text References
Beuzelin JM, Reagan TE, Way MO, Mszros A, Akbar W, Wilson LT, 2011. Potential impact of Mexican rice borer non-crop hosts on sugarcane IPM. International Sugar Journal, 113(1353):660-665. http://www.agra-net.com
Institute of Pacific Islands Forestry. 2009. Pacific Island Ecosystems at Risk.
Miller, J.H. 2003. Nonnative invasive plants of southern forests: a field guide for identification and control. FAO, 2012. Grassland Species Profiles. Grassland Species Profiles. Rome, Italy: FAO. http://www.fao.org/ag/AGP/AGPC/doc/GBASE/Default.htm
Gen. Tech. Rep. SRS-62. Asheville, NC: U.S. Department of Agriculture, Forest Service, Southern Research Station. 93 pp (USDA SRS).
González-Ibáñez J, 1987. Pre- and post-emergence control of Vasey grass (Paspalum urvillei Steud.) with several herbicides. Journal of Agriculture of the University of Puerto Rico, 71(2):233-234.
Ishimine Y, Nakama M, Matsumoto S, 1987. Allelopathic potential of Paspalum urvillei STEUD., Bidens pilosa L. var. radiata SCHERFF., and Stellaria aquatica SCOP., dominant weeds in sugarcane fields in the Ryukyu Islands. Weed Research, Japan, 32(4):274-281
Naresh JS, Smith CM, 1984. Feeding preference of the rice stink bug on annual grasses and sedges. Entomologia Experimentalis et Applicata, 35(1):89-92.
Newman, Y. C., Sollenberger, L. E., 2005. Grazing management and nitrogen fertilization effects on vaseygrass persistence in limpograss pastures.Crop Science, 45(5) 2038-2043.
Okayama L, 1989. The challenge of weed control in transplanted fields. In: Creativity, commitment, cooperation: tools for advancement. Hawaiian Sugar Technologists 47th annual conference reports, Honolulu, Hawaii, USA, 14-16 November, 1988. Aiea, Hawaii, USA: Hawaiian Sugar Technologists, A31-A33.
Phillips, R. L., Tucker, D. P. H., 1974. Control of problem weed species in Florida citrus with glyphosate.Proceedings of the Tropical Region, American Society for Horticultural Science, 18116-122.
Online Resources
https://www.cabidigitallibrary.org/doi/10.1079/cabicompendium.109621
Search Online
Google Search: Paspalum urvillei
Google Images: Paspalum urvillei
NatureServe Explorer: Paspalum urvillei
USDA Plants: Paspalum urvillei
Invasive Plant Atlas of the United States: Paspalum urvillei
Bugwood Network Images: Paspalum urvillei
