City Trees is a premier publication focused on urban + community forestry. In each issue, you’ll learn how to best manage the trees in your community and more!
Issue link: http://read.dmtmag.com/i/566672
A temporary road constructed to reduce soil compaction in the Critical Root Zone allowed construction vehicles to work between two mature trees. Step 1. Perform a tree inventory and assessment Human Nature, Inc., a regional landscape architecture and environmental planning firm who authored the Washington Park Master Plan and whose staff served as the project's park designer/landscape architect, was charged by the owner and local stakeholders to ensure that mature trees were protected over what would be almost two years of constant earthmoving and grading, underground utility line installation, and building construction. I was retained as the project's consulting arborist and was asked to inventory, assess, and photograph every tree in the park. Dutifully—yet in shock for being proac- tively requested to do this task!—I performed a detailed condition and basic risk assessment for 118 trees rang- ing in diameter from 9 to 52 inches (23 to 132 cm). I provided the landscape architect with the tree data to assist the firm in creating the final design and construc- tion documents. Step 2. Assess impact of the construction activity and specify measures needed for tree protection and stress reduction Armed with valuable tree inventory information, Human Nature collaborated with me to understand how the proj- ect would affect these public trees and vice versa. While the initial goal sought by the City and its citizens was to preserve every tree, the tree evaluation confirmed this was unrealistic. The inventory information I provided helped the landscape architect and engineers make reasonable decisions based on science and better manage the expectations of owners and stakeholders. Some trees were in poor vigor and were destined to die in a few years regardless of the future construction; others were structurally unsound and needed to be removed for public safety. Many other trees, however, were in great condition, and the park would lose majes- tic trees providing important benefits unless protection measures were taken. So, the construction drawings were analyzed again. This time the condition and Critical Root Zones and Structural Critical Root Zones of significant trees were compared to the planned infrastructure priorities, giving all parties a new and more complete perspective on how trees could be made part of the overall plan. Step 3. Modify design elements and construction plans and procedures as needed As a result of this collaborative dialogue between arbo- riculture, engineering, and landscape professionals, agreement was reached to remove some trees to ease 22 City Trees