Growth and survival of provenances of snow gums (Eucalyptus pauciflora) and other hardy eucalypts at three trials in England.

摘要

Three trials of snow gums (Eucalyptus pauciflora) and other cold-tolerant eucalypts, planted in 1985, were assessed for height, diameter at breast height and survival. The trial sites were in southern England but differed in their climate, particularly maritime influence, summer moisture deficit, and in their altitude and soils. Patchy survival and windthrow within the trials posed constraints on the identification of trees of different locations (origins) that performed better. There were, however, some origins that showed good growth and survival across two or three trials. E. pauciflora ssp. debeuzevillei from Mount Ginini (Australia) showed superior growth and survival at Thetford (East Anglia) and Torridge (Devon), while E. pauciflora ssp. niphophila from Mount Bogong (also Australia) exhibited high survival across all three trials. If biomass production is the objective, many of the origins are too slow growing and faster growing species are available, including other eucalypts. The Mount Ginini origin of E. pauciflora ssp. debeuzevillei was estimated to produce 7 m3 ha-1 y-1 at Thetford and 10 m3 ha-1 y-1 at Torridge at 26 years old, while Sitka spruce is estimated to yield 13 m3 ha-1 y-1 on a similar rotation. A eucalypt species other than snow gum that showed some promise was E. perriniana, origin 'Smiggin Hole' (New South Wales, Australia) which yielded a mean annual increment of 25 m3 ha-1 y-1 over 24 years at Chiddingfold (Sussex). However, survival was poor at Thetford and so it may be suited to only the warmest of sites (above accumulated temperature (AT5) of 1900).