Buffelgrass
Pennisetum ciliare

Description: Buffelgrass (Pennisetum ciliare) is a drought-tolerant, warm-season, perennial forage grass which is grown throughout many arid and semi-arid regions in the world.1 It usually has a bushy stem that grows up to four feet tall and a mass of long and tough roots which can grow to eight feet deep. Its narrow leaves are light green in color and range from one to four inches in length.2

Habitat: P. ciliare is very successful in regions where annual precipitation ranges between 330-550 mm (13-22 inches) and the minimum winter temperature does not fall below 5(C (41(F). In its introduced range, buffelgrass is most abundantly found in the plains of the Sonoran Desert, where it is commonly found along rocky hillsides in desertscrub and xeroriparian communities near planted pastures and roadways.3 Roadways are a good source for the spread of buffelgrass because they provide water from runoff and are infrequently grazed.

Total Range: Buffelgrass is native to arid and semi-arid regions of Africa, Asia and the Middle East. It has been introduced outside of its native range as early as 1880 in Australia and 1917 in Texas.3 The most prevalent variety of P. ciliare in North America was collected in north-central Kenya during the 1940's and established in San Antonio, Texas, by the U. S. Department of Agriculture Soil Conservation Service. This variety was also introduced into California, Arizona and Mexico.4

Threat to Native Species and/or Environments: Buffelgrass loves fire and needs it to maintain a healthy population. It will even burn while its still green and forms new sprouts immediately after the flames die down.4 By comparison, most native desert plants cannot survive fire. Once its competition has died, buffelgrass will move into the new territory and choke out all other plants, creating an area dominated by one species. This, in turn, has a profound effect on native animal species, especially grassland bird species.

Buffelgrass in Pima County: P. ciliare arrived in Tucson shortly before 1940, where it was studied at the Soil Conservation Service's Tucson Regional Conservation Nursery, now know as the Natural Resource Conservation Service-Tucson Plant Materials Center. In 1973 and 1974, buffelgrass was planted along with several other non-native and native species on the Caterpillar Proving Grounds, near Green Valley, to "determine species and cultural practices best suited for establishment of vegetative cover on areas disturbed by construction."5 In 1979, this species was planted on the slopes of the City of Tucson channel near the Tucson Plant Materials Center to evaluate its ability to stabilize erodable slopes.5 From 1982 to 1986, buffelgrass was successfully planted at the Santa Rita Experimental Range, where it continues to thrive to this day. This "invasive" species has since shown up in several areas around Tucson, including Tumamoc Hill, the Tucson Mountains and the Saguaro National Mounument.4

References

1 Jessup, R.W., Paterson, A. H., Burson, B. L., Wang, Y. W. and Hussey. M. A. January 17-21, 1999. A detailed linkage map of buffelgrass. Plant & Animal Genome VII Conferance, San Diego, CA. http://www.intl-pag.org/pag/7/abstracts/pag7522.html

2 Douglas King Co. 1999. Grass Seed: T4464 Buffelgrass. www.dkseeds.com/grasssd.html

3 Miller, M. E., Burquez, A. and Martinez-Yrizar, A. 1999. Grasslandification in the Sonoran Desert: the case of Pennisetum ciliare.

4 Yetman, D. and Burquez, A. 1994. Buffelgrass - Sonoran Desert Nightmare. The Arizona Riparian Council newsletter. Vol. 7, No. 3, pp. 1, 8-10.

5 Rutman, S. 1999. History of buffelgrass in Arizona.