If you start looking around Clackamas County, it won’t take you long to find the invasive tree-of-heaven (Ailanthus altissima). This state-listed noxious weed is increasingly more common in many of our urban areas where it flourishes. Tree-of-heaven seems right at home in alleys, roadsides, railways, vacant lots, that crack in the sidewalk. Very large trees can also be found growing in many yards and vacant lots, where these trees were intentionally planted as ornamental. These large trees can reach heights up to 80 feet in height and can spread seed for blocks around.
In recent weeks, we have received a large number of calls, emails, and hotline reports following a recent news story about tree-of-heaven. This news account documents the trials of one local resident, as he struggles to deal with a tree on his property line that is slowly destroying his home’s foundation.
The threat from tree-of-heaven is real! If you have tree-of-heaven growing on your property, you should take action now to prevent further damage.
Small seedlings and saplings can be removed. The Clackamas SWCD WeedWise program has weed wrenches and other tools available through our equipment library at no cost to help you safely remove these small trees. So contact us today to reserve a weed wrench today.
Larger trees are much more difficult to manage. These large trees have extensive root systems that can spread up to 50 feet in all directions. Cutting large trees causes these roots to sucker, potentially leading to even more damage. An Integrated Pest Management (IPM) approach is needed to effectively manage tree-of-heaven. An IPM approach utilizes several different management strategies to be effective. To assist Clackamas County residents through this process we have published a Tree-of-heaven Best Management Practices (BMP). This document will help guide you through the management process.
Take action now! It isn’t too late to protect your home from tree-of-heaven.