Scoring system for crown distance adapted from International Co-operative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests, 2010).
The guidance recommends starting with the tree standing closest to the sample tree. In a clockwise procedure, score values are averaged. Dead trees are taken into account as long as they are in the crown condition sample.
Calculation: (Score 1 + Score 2 + Score 3 + Score 4)/4=CDRD
| Score | Class | Definition |
|---|---|---|
| 1 | Cramped | Canopies overlap |
| 2 | Closed | Crowns touch one another |
| 3 | Loose spread | Gap between crowns up to one-third of average crown diameter |
| 4 | Spread | Gap between crowns up to two-thirds of average crown diameter |
| 5 | Distant | Gap between crowns from two-thirds up to one whole of average crown diameter |
| 6 | Very distant | Gap between crowns > 1/1 of average crown diameter |
| Download an Excel workbook containing tree assessment tables found in the stormwater manual. | ||