Ancient woodland

In the United Kingdom, ancient woodland is that which has existed continuously since 1600 in England, Wales and Northern Ireland (or 1750 in Scotland).^[1][2] The practice of planting woodland was uncommon before those dates, so a wood present in 1600 is likely to have developed naturally.^[3]

In most ancient woods, the trees and shrubs have been felled periodically as part of the management cycle. Providing that the area has remained as woodland, the stand is still considered ancient. Since it may have been cut over many times in the past, ancient woodland does not necessarily contain trees that are particularly old.^[1]

For many animal and plant species, ancient woodland sites provide the sole habitat. Furthermore, for many others, the conditions prevailing on these sites are much more suitable than those on other sites. Ancient woodland in the UK, like rainforest in the tropics, serves as a refuge for rare and endangered species. Consequently, ancient woodlands are frequently described as an irreplaceable resource, or 'critical natural capital'.^[4] The analogous term used in the United States, Canada and Australia (for woodlands that do contain very old trees) is "old-growth forest".^[5]

Ancient woodland is formally defined on maps by Natural England and equivalent bodies. Mapping of ancient woodland has been undertaken in different ways and at different times, resulting in a variable quality and availability of data across regions, although there are some efforts to standardise and update it.^[6]