Biomass production of Prosopis alba clones at two non-irrigated field sites in semiarid south Texas.
Three clones (1 P. alba and 2 P. alba × P. glandulosa var. torreyana) and an open-pollinated P. alba family, previously identified as high-biomass producers, were compared at 3×3-m spacing in two field trials (mean annual rainfall 525 and 700 mm respectively). At the drier site, 88%, 91%, 96% and 98% survival was recorded after 2 yr, despite a freeze of -12°C in the first winter and a 6-month drought in the second year during the hottest part of the year. Standing biomass at the drier site after 3 growing seasons was up to 7.39 t/ha. At the wetter sites one clone had standing biomass of 39 t/ha after 3 growing seasons. Results are discussed in relation to damage by deer and blister beetles (Epicauta nigritarsus), and differences in fertility and rainfall.