A New Method of Health Assessment for Prunus cerasifera ‘Atropurpurea’ on a Neighbourhood Scale in Vancouver
By Jonathan Leung
Junior Category (Grades 7-8)
Study | Biology
We look at the health assessment of Prunus cerasifera ‘Atropurpurea’, commonly known as Pissard plum in the Vancouver Arbutus Ridge area. Various sick tree characteristics including tree wounds and decays are first described. Tree decay detection tools are then discussed. We evaluate the use of infrared camera and the sounding mallet and decide the diameter at breast height (DBH), tree height and crown density offer the most accurate
measurements.
We propose an empirical formula that combines these 3 parameters into a health index value. 105 Pissard plum trees are measured and the associated health indices are calculated and plotted on the map. We further separate the trees into 3 separate groups based on 3 circumference sizes: ≤ 60 cm, 60-100 cm and > 100 cm and calculate the average health index of each group. Although the smallest circumference group has the largest health index value, the largest circumference group has a higher health index than the medium circumference group.
We find the circumference may not be a good measure of the tree age. Depending on the environment, previous wounds and damages and genetic characteristics, some younger trees may have a larger circumference than the old trees. Finally, we discuss adding other tree parameters to our health index formula to improve the tree health assessment coverage.
