Removing Tree of Heaven
The invasive Tree of Heaven (Ailanthus) continues to spread into residential areas of the Old Towne area near Jewel Park up to the Boulevard district. Resident who try to remove the tree discover quickly that they return ten-fold. This article goes over proven ways to remove the tree depending on the size.
For mature trees we use hack and squirt method using Triclopyr.
A few key points w/this method:
* Timing is critical. The best treatment window is mid-July through early October, when the tree is moving sugars down into its roots. That’s when the herbicide is carried into the entire root system. Treating in spring is much less effective because sap is moving upward.
* Don’t cut the tree down first. If you cut a Tree-of-heaven before treating it, it often responds by sending up dozens or even hundreds of root sprouts many feet away from the original tree. Most extension services recommend waiting at least 30 days after herbicide treatment before removing the tree.
* Triclopyr is commonly used. For hack-and-squirt, experts generally recommend the amine formulation of triclopyr (water-based), not the ester formulation that’s used for basal bark treatments. Glyphosate is another effective option, but triclopyr is often preferred for Tree-of-heaven.
The basic hack-and-squirt process is:
1. Make downward-angled cuts (“hacks”) into the cambium with a hatchet.
2. Leave intact bark between the cuts—don’t girdle the tree.
3. Immediately place herbicide into each cut until it’s filled but not running down the trunk.
4. Leave the tree standing for at least a month (many people leave it until winter) before felling it.
Note: For small seedlings and saplings (generally under 3–6 feet tall) a foliar spray can be used, it thoroughly wets the leaves without affecting nearby desirable plants.
For small to medium trees (roughly up to 6 inches in diameter): A basal bark treatment can be sprayed around the lower 12–18 inches of the trunk, where it penetrates the bark and moves into the roots.
