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THE DEVELOPMENT OF TREE COMMUNITIES AT STAVERTON PARK AND THE THICKS, WANTISDEN N. E. SIBBETT Staverton Park and the Thicks is a mediaeval deer park of international nature conservation interest. It contains thousands of ancient gnarled oaks, together with many hollies and some rowan trees. There is a wide ränge of organisms of special interest, mostly connected with the dead wood or the continuity of treetrunks as a substrate. Staverton Park and the Thicks contains a wide ränge of rare deadwood invertebrates (JNCC 1993), a rare fungus, Buglossoporus pulvinus (Pers. ex Pers.) Dunk. (Holden, 1985; Ted Green, pers. comm. 1995), rare lichens e.g. Lecanactis abietina (Ach.) Körber (Chris Hitch, pers. comm. 1993, 1997) and a rare liverwort, Pallavicinia lyellii (Hook.) Carruth. (Richard Fisk, pers. comm.). Staverton Park itself contains widely-spaced oak trees but few other trees. The Thicks, which is adjacent, has an enormous number of tall hollies which are mostly found growing from the base of the ancient oaks. There are a number of views on the origin of the distinct oak/holly relationships. This paper is a contribution to that debate. Peterken (1969) believed that the difference between the two parts of the original deer park was caused by a change in management. Before the mid nineteenth Century, the whole park was grazed and there was little tree regeneration. About 150 years ago the area now called the Thicks was sold separately, and the new owners excluded livestock. As a result, seedling hollies were able to grow up and are the tall trees of today. Peterken also carried out tree ring analysis and decided that the hollies were indeed around 150 years old, with the oaks being much older. However, he doesn't comment on the hollies being found predominantly growing from the base of the old oaks. In recent years, the concept of 'bündle planting' has gained prominence. Several trees were believed to have been planted in the same planting hole, in Order to speed up the development of a large crown. The hollies and oaks at the Thicks have been proposed as examples of 'bündle planting', perhaps so that the prickly hollies would protect the growing oaks from browsing animals (Green, 1994, 1996). To help investigate these theories, it is necessary to investigate further. One approach is to search for modern Vegetation that could be similar to the precursor Vegetation of the Thicks. In Staverton Park, despite heavy deer browsing, it is possible to find young (i.e. up to ten years old) holly growing from the base of old oaks. 1 speculate that deer and other livestock may not like to browse from the base of old trees, perhaps because their vision becomes blocked. It seems reasonable to imagine that 150 years ago there were more holly seedlings, following a good seeding year and/or with reduced grazing pressure. When grazing stopped in the Thicks these hollies grew into the trees of today. Further speculation arises from Peterken's discovery through tree ring analysis (Peterken, 1969) that the oldest oak branches were about the same age as the hollies, indicating major pollarding at the same time. It is common for pollarded branches to be stacked against their tree trank to allow them to
Trans. Suffolk Nat. Soc. 33 (1997)