Sampling efficiency evaluation in Emory oak woodlands of southeastern Arizona

Abstract

A forest inventory was made by a two-man team in the Emory oak (Quercus emoryi) woodlands, near the Huachuca Mountains, in southeastern Arizona. Two plot sizes, 1/10th, and 1/25th hectare, and three basal area factors, 2, 4 and 6 (square meters per hectare) were used. Tree tally time was recorded, but the travelling time between plots was not recorded. Total number of trees, total basal area, and total volume of trees per hectare were measured, summarized, and analyzed. Significant differences were noted between plot sampling and point sampling. Results suggested that with plot sampling, 1/25th hectare plot was more efficient than 1/10th hectare plot for all measures of forest densities. With point sampling, basal area factor 6 had the highest relative sampling efficiency in terms of trees per hectare. Basal area factor 2 had the highest relative sampling efficiency in terms of basal area and volume per hectare. From this information, more efficient forest inventories of the Emory oak woodlands can be designed.