Arboriculture
Management of individual trees or groups of trees primarily for their amenity value.
Clean Out
This is the removal of all dead, dying and diseased branches; in addition branches that are crossing one another are removed and climbing plants like ivy.
Arborist
A contractor skilled in performing aerial operations in trees, as is often necessary near buildings and roads.
Conservation Area
Section 69 of the Civic Amenities Act 1967 gives local councils the power to designate as Conservation Areas, "areas of special architectural or historic interest, the character or appearance of which it is desirable to preserve or enhance".
Pollarding
This involves the removal of whole branches to leave only the main trunk. In species such as willows and poplars, significant pruning is acceptable with new branches developing from the pollard heads. Secondary pruning of the new wood can help form a new canopy to the tree several years after the initial pollard.
Amenity Value
The environmental and landscape benefits of trees as opposed to their commercial value for timber.
Crown Reduction
A pruning method which reduces the length of each branch to to reduce the whole size of the tree canopy, not just the height, but the whole circumferance. This is usually calculated in percentages, I.E, 10, 15, 20% etc. The aim is to leave a well balanced, natural looking tree. When the reductrion has taken p[lace, all dead wood and rubbing branches are removed.
Crown Lifting
Involves the removal of lower branches to provide a desired amount of clearance above ground level. This can be achieved either by the complete removal of a branch or only parts of which extend below the desired height.
Root Protection Area (RPA)
The RPA of a tree is the area around its base that contains sufficient rooting volume to ensure the survival of the tree in the event of nearby soil disturbance (as on a development site). The RPA is calculated using guidelines in BS 5837 (2005) Trees in relation to construction - Recommendations.
Tree Preservation Order (TPO)
A Tree Preservation Order (TPO) is an order made by Councils which generally makes it an offence to cut down, lop, top, uproot, willfully damage or willfully destroy a tree without first getting permission. Tree Preservation Orders are usually made to protect trees that make a significant contribution to the amenity of an area.
