There is growing evidence and concern that increasing levels of greenhouse gases in the atmosphere will increase global temperatures. Temperatures in the UK may increase by 3δC± 1.5δC over the next 70 years † The tree crop is sensitive to such large and rapid climatic change because of its longevity. This paper reviews (1) changes that might occur in the forest environment, including soil, following climatic warming; (2) past and future long-term changes in the species composition of UK forest; (3) possible positive and negative effects.of climatic warming on the growth and yield of UK forests; and (4) the vulnerability of forests to any change in the frequency of extreme events.