Influence of climatic and edaphic factors on the distribution of eragrostis lehmanniana nees in Arizona, USA

Abstract

Lehmann lovegrass (Eragrostis lehmanniana Nees) was introduced into Arizona, USA, from South Africa in 1932 and has since been sown throughout the southwestern USA and Northern Mexico. The species is well adapted in southeastern Arizona where it has been sown on over 69 115 ha and has spread by seed to an additional 76 040 ha. Where Lehmann lovegrass predominates and spreads, surface soils are sandy, summer rainfall is greater than or equal to 200 mm and winter temperatures rarely fall below 0° C. Factors contributing to the spread of Lehmann lovegrass in southeastern Arizona include fire, cattle grazing and drought.