Effect of seedling characteristics at planting on browsing of Eucalyptus globulus by rabbits

Abstract

Summary We investigated the effect of Eucalyptus globulus seedling characteristics, particularly height and diameter at planting, on the extent and severity of browsing damage by rabbits in a plantation field trial. In the first month following planting, browsing was negligible on tall (27 cm), large-basal-diameter (6.2 mm) open—rooted 'half and half E. globulus seedlings compared with normal container stock (height 16–17 cm; basal diameter 1.9 mm) or tall container stock (height 27 cm; basal diameter 2.5 mm). After 4 mo, survival was 96% for the open-rooted seedlings, but only around 75% for the other types of seedling. Survival and growth rate of open-rooted stock decreased between 4 and 14 mo after planting. This was not a result of browsing, but was probably due to drought stress. We also investigated the use of a commercial repellent, ‘Multicrop Scat’, on rabbit browsing. The repellent did not reduce browsing, but appeared to have a beneficial, though not statistically significant, effect on growth and survival. Results indicate that large open-rooted seedlings could be used to reduce the detrimental impact of rabbit browsing on plantation establishment. Benefits of using these seedlings may need to be balanced against risks associated with reduced survival in periods of low rainfall following planting.