Growth ofProsopis caldeniaseedlings in the field as related to grazing history of the site and in a greenhouse as related to different levels of competition fromStipa tenuis

In temperate semi-arid rangelands of Argentina grazing by domestic livestock is apparently linked with the conversion of open grasslands to dense shrublands.Prosopis caldeniaandStipa tenuisare dominant species of the shrub and grass life-forms, respectively. Research was conducted to determine the growth responses ofP. caldeniaseedlings to grazing history of the site and competition fromS. tenuis, at different levels of water availability. TheProsopisseedlings grew better (p<0•05) in long-term protected than in long-term grazed sites, and at low rather than high levels of competition fromS. tenuis. Both overgrazing and high levels of grass competition may limit the establishment ofP. caldeniaseedlings in grasslands, particularly under conditions of water shortage.