A Comparison Between European Continental and British Provenances of Some British Native Trees: Growth, Survival and Stem Form

Abstract

Data describing the growth, survival and stem form of: a) European continental, and b) British provenances of trees native to Britain were collated from Forestry Commission records. The growth rates of European continental provenances of Scots pine ( Pinus sylvestris ), silver birch ( Betulo pendula ), sessile oak ( Quercus petraea ) and common alder ( Alnus glutinosa ) were inferior to those of British provenances in 90 per cent of cases. European provenances of these species also showed inferior survival. The growth rates of continental provenances of beech ( Fagus sylvatica ) were superior to British provenances in about 50 per cent of cases, provenances from northern France, Belgium and Holland being the fastest growing. Relationships between the relative height growth of foreign provenances and latitude were demonstrated for Scots pine, silver birch and beech (relative height growth = the height growth of a foreign provenance expressed relative to that of British provenances at the same site). The continental provenances that grew best originated at 0–4° south of the latitudes of the planting sites. Relative height growth decreased both north and south of these latitudes. In the case of oak, relative height growth did not vary widely between origins. The survival of continental provenances of Scots pine was particularly poor on exposed upland sites. The stem form of British provenances of Scots pine was intermediate between Fennoscandian provenances and provenances from the rest of Europe. In oak and beech there was generally little difference in stem form between British and continental provenances, but the best continental provenances (Belgian beech; French oak) were most reliable. The growth and survival of native trees is interpreted in the light of the post-glacial history of these species. The implications regarding the continued use of seed of native hardwoods imported from continental Europe are discussed.