Screening Prosopis (Mesquite or Algarrobo) for Biofuel Production on Semiarid Lands1

Assistant Research Scientist, Caesar Kleberg Wildlife Research Institute, Texas A&I Univ., Kingsville, Texas; Staff Research Associate, Professor of Soil Physics, and Staff Research Associate, University of California, Riverside, Riverside, California. Abstract: Eighty collections of Prosopis have been screened in field experiments for biomass production, frost tolerance, and heat/drought tolerance. Selections have been examined in the greenhouse for nitrogen fixation and salinity tolerance in which one species grew on a nitrogen free media in salinities equivalent to seawater. A 44 percent sugar pod producer was identified and successfully fermented to ethanol by Avgerinos and Wang at MIT. Individual trees have grown 5 to 7 cm in basal diameter and 2 to 3.2 meters in height per year with 600 mm total water application. Dry matter production of 14,000 kg/ha has been obtained at projected harvested costs of $23.00 per ton or $1.35 per million Btu and compare favorably with natural gas, heating oil, and coal at $3.0, and $6.0, and $1.50 per million Btu's respectively.