What is a Preliminary Tree Assessment?
When should a Preliminary Tree Assessment be carried out?
What does the Preliminary Tree Assessment need to be co-ordinated with?
What sort of information is included within a Preliminary Tree Assessment?
General information collected for each individual tree should include: a tree number, botanical name, height, canopy spread, age class, tree significance, useful life expectancy, priority for retention, trunk diameter at breast height (DBH), tree protection zone (TPZ) and structural root zone (SRZ). The preliminary tree assessment should also include a tree location plan prepared using CAD or ArcGIS software. The tree location plan will show the number and location of each tree, the extent of the tree protection zone and should be colour coded to show the retention value for each tree (low, medium or high priority for retention).
The information contained within a preliminary tree assessment is used by planners, architects and designers, in conjunction with any planning controls and other legislation, to develop the design layout in such a way that trees selected for retention are provided with enough space to remain viable. The tree retention value will assist in prioritising which trees should be retained and protected, while the tree protection zone will provide the necessary offsets to protect those individual trees.