Things You'll Need
Spray or paint brush
Also called Chinese sumac or tree of heaven, the ailanthus tree (Ailanthus altissima) was initially used as a landscaping plant in alkaline soils and areas with extreme drought. Later, the tree was found to disrupt sewer systems, produce toxins that inhibited other plants from growing nearby and it bore foul-smelling fruit. It is an invasive plant species most people avoid growing in their yards. Remove the stump and roots of the tree as well to keep it from growing back in your garden.
Pull out young seedlings from your garden or yard as soon as they are large enough to grasp, before their taproots develop. Moisten the soil to make it workable, grasp the stem firmly and pull the undesirable tree of heaven seedling out from the soil along with its roots.
Collect broken roots from the planting hole and discard to keep the seedling from resprouting. Add quality topsoil to the hole and grow your desired plants there.
Trim an ailanthus sapling down to the ground using a tractor-mounted mower, preferably when it begins to flower. Although you need to repeat the process every time the young plant emerges from the soil, repeated mowing exhausts food reserves in the underground parts of the young tree, making it vulnerable to chemical foliar sprays.
Girdle a large ailanthus tree during spring when it is actively growing. Using a hatchet, form 1-inch-long, 2-inch-wide and 1/2-inch-deep cuts or notches around the trunk of the tree.
Spray or apply glyphosate herbicide over the cuts. If spraying the herbicide, direct the nozzle of the sprayer over the exposed cambium tissue and ensure complete coverage. The chemicals penetrate the tree and translocate to the roots, causing it to die. Wipe excess spray that runs down the trunk to keep it from falling over the grass below.
Dig a trench 2 feet away from the base of the tree. Keep it as deep as required to expose dead or dying roots. Insert a shovel under the root ball to pry it out of the soil. Rock the tree back and forth to break the roots that hold it in the soil so it is easier to remove.
Another way to kill an ailanthus tree is to fell it to the ground. Use a handsaw or chainsaw to cut the trunk as close to the ground as possible. Apply glyphosate herbicide over the exposed surface of the stump or bore holes through it and pour the herbicide into each.
- California Invasive Plant Council; Ailanthus Altissima; John Hunter
- Arizona Cooperative Extension; Tree of Heaven; Jeff Schalau; November 2007
- Plant Conservation Alliance's Alien Plant Working Group: Tree-of-Heaven
- Arizona Cooperative Extension; Invasive Weed Trees; Jeff Schalau; 2001
- Invasive Species Fact Sheet; Tree-of-Heaven; Ann F. Rhoads, et al.; April 2002
- OSU; Controlling Undesirable Trees, Shrubs, and Vines in Your Woodland; Randall Heiligmann