Evaluate Your Site
A Guide to Site Analysis for Street
species vary considerably in their minimum requirements for rooting volume,
soil pH, drainage, etc. A site evaluation will allow you to choose the
very best trees for a given location. Without a site evaluation, communities
often choose a tree species that will handle the worst possible site conditions
as a safeguard against tree failure. The result of this practice is the
overuse of a few highly tolerant “bread and butter” species,
such as Bradford pears. These few species are not only monotonous, but
can create catastrophic problems when a new pest arrives, or when problems,
such as poor branching structure, are identified. It is good practice
to always seek to diversify the tree species composition of a community.
A good site evaluation is an essential tool in species diversification.
A thorough site evaluation should tell you how well a proposed planting
site will be able to support street trees and what specific site limitations
are. The Tree Selector’s Site
Evaluation Form will guide you through this process. After the site
evaluation is complete, select appropriate species
and cultivars. The specific site for each tree should be considered to
make sure a plant selection is made that will thrive in that spot.
Some site improvement can be made in many cases. You may need to Modify
Your Site with subsoiling, tilling, grading, drainage, soil amendments,
soil replacement, or other site preparations. Plants should then be selected
that can tolerate the current or improved site conditions. Adapting the
planting design to counteract site problems and better accommodate trees
can also relieve some site limitations. Careful coordination of site conditions,
tree selection and design adaptation will improve success.