To Control The Ailanthus Tree (Tree Of Heaven)

On August 03, 2020

To Control The Ailanthus Tree (Tree Of Heaven)


With the issue of COVID 19 virus impacting everyone’s life, the Spotted Lantern Fly (SLF) has fallen off the radar of many people. However it remains a major threat to agricultural crops and trees. An SLF quarantine is currently in effect for 26 counties in Pennsylvania. More counties may be added to the quarantine if additional populations of SLF are confirmed. If you find a spotted lanternfly, kill it and report it immediately with the Pennsylvania Department of Agriculture’s online reporting system or by calling 1-888-4BAD-FLY (1-888-422-3359).


The Tree of Heaven is a preferred host tree for SLF, and current management efforts are focused on removing it or using it as a trap tree by treating it with insecticide. This tree is native to both northeast and central China, as well as Taiwan. Spotted Lanternfly, an invasive pest, is particularly attracted to Tree-of-heaven.


Tree-of-heaven was first introduced into the United States in the Philadelphia area in 1784. It can reach up to 100 feet tall and 6 feet in diameter. The bark of mature tree-of-heaven looks similar to the outside of a cantaloupe. When crushed, the leaves and stems have a foul odor that many describe as rotten peanut butter. They spread by seed and will also produce “clones” by their roots. This tree can be mistaken for other native species, including black walnut, hickory, and staghorn sumac. For help identifying and treating this plant, visit the Penn State Extension spotted lanternfly website.


Tree-of-heaven leaves are pinnately compound, meaning they have a central stem in which leaflets are attached on each side. One leaf can range in length from 1 to 4 feet with anywhere from 10 to 40 leaflets. The leaflets are “lance” shaped with smooth or “entire” margins. At the base of each leaflet are one to two protruding bumps called glandular teeth. When crushed, the leaves and all plant parts give off a strong, offensive odor.


This species is easily confused with some of our native species that have compound leaves and numerous leaflets, such as staghorn sumac, black walnut, and hickory. The leaf edges of these native trees all have teeth, called serrations, while those of tree-of-heaven are smooth. The foul odor produced by the crushed foliage and broken twigs is also unique to tree-of-heaven.


Due to its extensive root system and resprouting ability, tree-of-heaven is difficult to control. Treatment timing and following up the second year are critical to success. Mechanical methods, such as cutting or mowing, are ineffective, as the tree responds by producing large numbers of stump sprouts and root suckers. When cutting tree-of-heaven is necessary to remove potentially hazardous trees, it is best to treat with an herbicide first, allow 30 days for it to take effect, and then cut.

Hand pulling young seedlings is effective when the soil is moist and the entire root system is removed. Small root fragments are capable of generating new shoots. Seedlings can be easily confused with root suckers, which are nearly impossible to pull by hand.

To control tree-of-heaven, target the roots with systemic herbicides applied in mid- to late summer (July to onset of fall color) when the tree is moving carbohydrates to the roots. Herbicide applications made outside this late growing season window will only injure aboveground growth. Following treatment, repeated site monitoring for signs of regrowth is critical to prevent reinfestation.

Herbicides applied to foliage, bark, or frill cuts on the stem are effective at controlling tree-of-heaven. Cut stump herbicide applications encourage root suckering and should not be utilized. Apply all treatments no earlier than July 1 up until the tree begins to show fall colors. There are many effective herbicides available for use on tree-of-heaven, including dicamba, glyphosate, imazapyr, metsulfuron methyl, and triclopyr. For most treatments we recommend using herbicides containing the active ingredients glyphosate or triclopyr.

Foliar herbicide sprays are used where tree height and distribution allow effective coverage without unacceptable contact with nearby desirable plants. Treatments are applied in mid- to late growing season with equipment ranging from high-volume truck-mounted sprayers to low-volume backpack sprayers.

Basal bark applications provide a target-specific method for treating tree-of-heaven that in general is less than 6 inches in diameter. Using a low-volume backpack sprayer, a concentrated mixture of herbicide containing the ester formulation of triclopyr in oil is applied from the ground line to a height of 12 to 18 inches, completely around the stem. To maximize translocation to the roots, apply herbicides from mid- to late summer.

Frill herbicide applications, called hack-and-squirt, are highly selective with a concentrated herbicide solution applied directly into the stem. For effective hack-and-squirt applications, apply the herbicide solution to spaced cuts around the circumference of the stem. Leaving uncut living tissue between the frill cuts allows the herbicide to move to the roots. Again, make applications in mid- to late summer.

Well-established tree-of-heaven stands are only eliminated through repeated efforts and monitoring. Initial treatments often only reduce the root systems, making follow-up measures necessary. Persistence is the key to success.

For help identifying and treating this plant, visit the Penn State Extension spotted lanternfly website:


To Plant Drought Emergency Fall Forages


Because of the drought conditions and the resulting less than anticipated forage growth, You may be wondering what alternatives farmers have for forage production once the drought breaks. Extension Agronomist Del Voight offers these suggestions. Farmers who graze may not have been able to produce sufficient hay/silage to get through the winter. For them, an option is to plant some forage crops in August (hopefully it will be raining again by then) that can provide grazing this fall and allow hay/silage to be made from their traditional pasture land.


For those who need pasture, Forage Brassicas (e.g. Rape or turnip):and Small Grains (e.g. wheat, barley, rye, or triticale) are options. Most of the crops that could be planted at this late time and produce some forage are better suited for harvesting as silage rather than hay. For those who do not need pasture options include Summer-Annual Grasses (e.g. Sorghum, Sudangrass, Sorghum-sudan hybrids, and Millet. Other options include Small Grains (Oats and Rye, use taller varieties). For more information consult the Penn State Agronomy Guide.

Quote of The Week: “I have only one yardstick by which I test every major problem – and that yardstick is: Is it good for America?” Dwight D. Eisenhower