6. Academic Quads and Courtyards about 1919
3 Tree Condition
For the past century, the Queen’s University campus has been blessed with a diverse population of trees and shrubs. This urban forest consists mainly of: Maple, Lindens, Black Locust, Oak, Austrian Pine, Fir, Spruce, Ash, Birch, Walnut, Crabapple, Beech, Turkish Hazel, White Pine, Elm, Cedar, Poplar, Chestnut, Gingko, Honeylocust, Basswood, Kentucky Coffee tree and various shrubs. It is difficult to place a value on this landscape as the mature trees have assisted in defining the character and image of the campus. More recent plantings are attempting to continue this contribution as well as provide many other benefits. The ice storm of 1998 has however, focused attention on the landscape. An overview of the urban forest has found the trees to be in various stages of decline--this is evident by the sparse crowns, deadwood, poor leaf size and colour and minimal annual growth. The health of many of these trees can be restored with the implementation of a Plant Health Care Program; however, an assessment of individual trees must be taken first to determine viability in this setting.
The arboricultural report to follow deals with the challenges of maintaining an urban forest in a stressful environment and the need for a replacement plan to upgrade the existing trees.
The high volume of cars, bicycles and foot traffic poses a less than ideal growing environment. Soil compaction prevents the root system from receiving water, nutrients and oxygen, resulting in the loss of life sustaining elements. Sidewalks and concrete have also lessened the soil surface, making this exchange difficult. Lawnmowers and weed-eaters have damaged tree trunks creating wounds. Excavation for buildings, street lighting and parking lots have cut and destroyed vital root systems. The alteration of grades around trees has smothered root systems. Trenching under the tree canopies has damaged root systems. Girdling roots are slowly killing the Norway Maples. Damage from the ice storm has destroyed the structural integrity of more than a hundred trees, leaving them unable to sustain life. Trees have been planted in beds which are too small to sustain a mature tree, planted too close to buildings and to other trees. Indiscriminate overplanting has cluttered up open space and the "middle plane" beneath the canopy and above the ground, masking buildings and sight lines needed for safety. These ills can be attributed to poor design.
While some of these conditions cannot be altered, others can be addressed in a positive way and managed successfully. A regular maintenance program including pruning, cabling, fertilizing, watering and insect and disease control will greatly improve the growing environment and assist in maintaining the vigor of the trees. Evidence suggested that trees that were maintained prior to the storm received less damage than those that were not maintained.
The root of the problem, a poor growing environment for trees, must be corrected to properly accommodate the needs of trees, people and vehicles. Pedestrians must be encouraged to use existing sidewalks and not create cow paths. Raised curb edges and low planter walls would also protect planting from traffic. The installation of more bicycle racks and stricter enforcement of bicycle regulations would eliminate the use of trees as bicycle stands. Removal of grass and the installation of mulch around the base of trees would prevent mechanical damage to tree trunks from lawnmowers and weedeaters and eliminate competition from grass. The implementation of planting specifications and the selection of trees that are suited for the particular sites will help to improve the success of replacement trees.