Frost damage to eucalypts in a short-rotation forestry trial in Cumbria (England)

Cold is the main climatic constraint to planting eucalypts in Britain and the winter of 2009-2010, the coldest in thirty years, proved particularly challenging for their survival. Damage to transplants planted in May 2009 of two species of eucalypts, Eucalyptus gunnii and Eucalyptus nitens, were assessed over the winter of 2009/2010 at a trial in Cumbria, northern England. Larger trees were found to have exhibited less cold damage by the end of January 2010, but by May there were no significant differences in survival due to tree size. By late January, there were statistically significant differences in damage between E. gunnii and E. nitens with the former being more cold tolerant. However, damage at the end of January, after minimum temperatures of -14 oC, did not appear serious, yet by May the survival of E. gunnii was 37% and for E. nitens was less than 1%. As larger trees exhibited relatively less frost damage it is recommended that intensive silviculture be practiced to ensure trees are between 1 and 1.5 m tall prior to their first winter to reduce the extent of damage through frost.