Estimation of Browse by Size Classes for Snowshoe Hare

Abstract

Mean stem weight and regression of weight on length were used to estimate available browse for snowshoe hare (Lepus americanus), and mean stem weight was used to estimate browse use. An initial set of stem weight data, followed by periodic field surveys, supplied estimates of the browse resource by species and by size classes within species. Field time of 30-45 minutes per stand, sampling 30 0.6-m2 plots with a 2-person crew, yielded mean estimates with standard errors of about 15% of the mean. Of the common browse species, roses (Rosa spp.) were most used by hares (12% of that available), and beaked hazel (Corylus cornuta) was least used (3%). The latter, however, produced 30 times more available browse than the rose species. J. WILDL. MANAGE. 44(1):34-40 Determination of the amount of woody browse available to animals and its use can be imprecise, time-consuming, or both. Methods vary from trained estimation (Pechanec and Pickford 1937) to clip-and-weigh. Modifications use average twig weight distal to point of browsing (Shafer 1963) or relate twig weight to diameter at point of browsing (Telfer 1969) to determine availability and/or