Mature mesquite (Prosopis glandulosa var. glandulosa) stand description and preliminary effects of understory removal and fertilization on growth

Abstract

The growth of a mature stand of Prosopis glandulosa was measured following understory removal, thinning, and phosphorus fertilization. Many of the 193 trees ha−1 were multi-stemmed at the base, with the result that there were 356 stems ha−1. The basal diameters ranged from 5·7 to 40·7 cm, with a mean of 16·4 cm. The trees were examined over three growing seasons using permanently mounted bands inscribed with a vernier scale capable of reading 0·25 mm increments. Regressions were used to convert basal area increases to volume and weight increases. Understory removal stimulated the greatest growth. Thinning multi-stemmed trees to a single stem with best form resulted in 33 m3 of firewood ha−1 The understory removal, plus herbicide resprout treatment, plus thinned, plus fertilizer had the greatest growth of; 0·86 m3 ha−1 in volume, 1890 kg/ha in green weight, and 0·61 cm in basal diameter over three growing seasons. Significant treatment differences (p = 0·05) were found between the growth of the control treatment and the (1) treatment with understory removal plus thinning and (2) the treatment with understory removal plus thinning plus fertilization.