Increasing range production from fodder shrubs in low rainfall areas

Abstract

Field experiments were conducted at the University of Jordan Research Station at Al-Muwaqqar village to develop a simple technique for establishing Atriplex seedlings, and to evaluate the browse production under natural precipitation compared with shrubs receiving additional harvested water. Overall survival of the transplants after three growing seasons averaged 67% under strictly rainfed conditions compared to 95% when additional harvested water of 39 mm was applied. Production of grazable browse of 3-year old shrubs averaged 380 and 1151 kg DM (dry matter) ha −1 without and with additional water, respectively. Rain use efficiency averaged 1.14 and 4.48 kg DM ha −1 year −1 mm −1 for strictly rainfed conditions and additional harvested water, respectively. Intensity of cutting had a highly significant effect on the potential of shrub regrowth. Cutting shrubs at a height of 15 and 30 cm above ground level reduced regrowth substantially, whereas cutting at 45 cm enhanced the amount of regrowth. The different cutting intensities had no significant effect on survival of the severed shrubs, which indicates the high tolerance of saltbushes to cutting or browsing. Water-harvesting contour furrows are reasonable for establishing saltbush plantations in low rainfall areas (100–200 mm). Additional harvested water in small amounts from macro-catchements had a substantial effect on shrub survival, biomass production and water use efficiency.