Forestry and woodland management is as rich in jargon as most other specialties. For the non-expert, the terminology involved can be just as confusing and off-putting. For that reason, the Royal Forestry Society has compiled this 2019 expanded edition of our popular glossary ‘Tree Terms’ to put tree-speak into plain English for non-professionals. More than 300 terms are here – some ancient, others modern. The latest version embraces a number of novel terms or concepts, especially on carbon certification and sustainability. Words in bold italics cross reference to terms elsewhere in the glossary. Commonly used abbreviations and acronyms are also listed.