Allometric Equations for Ashe Juniper (Juniperus ashei) of Small Diameter

Abstract

Abstract Native species of juniper are encroaching on grasslands throughout the Great Plains. Prescribed fire is often used to treat or prevent the early stages of encroachment, but little information is available about the contribution of small junipers to overall fuel loads. I sampled 33 individuals of Ashe juniper (Juniperus ashei) from grasslands on Fort Hood Military Reservation, Texas. The relationship between size and above-ground biomass differed for small and larger trees. I focused most of my analyses on small trees (<15 cm in basal diameter), which are most likely to burn in a prescribed fire. Allometric equations based on basal diameter (BD) or basal diameter and height (BD2H) predicted total biomass better than equations using only tree height, canopy area, or canopy volume (r2 = 0.95–0.97 versus r2 = 0.71–0.77). Living and total biomass for smaller fuel-classes (<25 mm in diameter) were more accurately predicted than dead biomass and larger fuel-classes (r2 = 0.94–0.98 versus r2 = 0.75–0.87)...