In the United Kingdom, an ancient woodland is a woodland that has existed continuously since 1600 or before in England, Wales and Northern Ireland. Planting of woodland was uncommon before those dates, so a wood present in 1600 is likely to have developed naturally.

The Celtic broadleaf forests are a terrestrial ecoregion that covers most of the islands of Great Britain and Ireland.

The Forestry Authority was a government research agency and a former branch of the non-ministerial government department the Forestry Commission of England and Scotland.

The English Lowlands beech forests are a terrestrial ecoregion in the United Kingdom, as defined by the World Wide Fund for Nature (WWF) and the European Environment Agency (EEA). It covers 45,600 km2 (17,600 sq mi) of Southern England, approximately as far as the border with Devon and South Wales in the west, into the Severn valley in the north-west, into the East Midlands in the north, and up to the border of Norfolk in the north-east of its range. The WWF code for this ecoregion is PA0421.

The Northern Forest is a proposed forest in England to encompass five community forests. The aim is to plant 50 million trees by 2032 which would provide a timber industry, leisure opportunities and environmental benefits. Initial funding for the project was granted by the British government in January 2018.

A royal forest, occasionally "Kingswood", is an area of land with different definitions in England, Wales, Scotland and Ireland. The term forest in the ordinary modern understanding refers to an area of wooded land; however, the original medieval sense was closer to the modern idea of a "preserve" – i.e. land legally set aside for specific purposes such as royal hunting – with less emphasis on its composition. There are also differing and contextual interpretations in Continental Europe derived from the Carolingian and Merovingian legal systems.

The Woodland Trust is the largest woodland conservation charity in the United Kingdom concerned with the creation, protection, and restoration of native woodland heritage. It has planted over 43 million trees since 1972.