Invasive Plants in Pennsylvania

Tree of Heaven

Ailanthus altissima

Description: Biology and Spread:

This rapidly growing tree can Tree of heaven spreads by reach a height of 80 feet, with hundreds of thousands of up to a six-foot diameter seeds per tree and through trunk. Leaves are pinnately vegetative sprouting. A cut or compound with 10 to 41 injured ailanthus tree may leaflets with smooth leaf send up dozens of root suckers margins. When crushed, the and resprouts, creating large leaves and other plant parts clonal colonies. have a rancid smell like cat urine or burnt peanut butter. Ecological Threat:

This tree produces chemicals in its roots that prevent the Photo: Jessica Sprajcar, DCNR establishment of other plant Background: species nearby. Its fast growth limits habitat for other species. Also known as Chinese sumac, Its root system may be stinking sumac and tree of Photo: Chuck Bargeron, U. Of Georgia, extensive and has been known www.invasive.org hell, this tree is native to Chi- to cause damage to sewer lines na. It was brought to Philadel- and building foundations. phia in 1784 by an amateur Flowering occurs in early gardener. By 1840 it was com- summer, when large clusters monly available from nurse- of yellowish flowers develop ries. Ailanthus is the subject above the leaves, Fruit of the well known book, “A produced on the female trees Tree Grows in Brooklyn,” by are tan to reddish, single winged, papery seeds, called Betty Smith. samaras. They may remain on the tree throughout late fall. Range:

Tree of heaven is very Habitat: common in the northeast and Midwest, through parts of the Ailanthus is extremely tolerant southeast, southwest and west of poor soils and will even coast. grow through cracks in pavement. Trees are not shade tolerant. They will Photo: Leslie Mehrhoff, U. of Connecticut, quickly colonize forest edges, www.invasive.org

fields and roadsides. Look-A-Likes: How to Control this Species:

The native trees most likely to Elimination of this species is Chemical be confused with ailanthus are difficult and time The most effective way to treat the sumacs (Rhus spp.). One consuming, due to its ailanthus is with herbicides. way to tell them apart is the abundant seed, high Foliar application of triclopyr small glands on the underside germination rate, and or glyphosate, mixed with of ailanthus leaves (see photo frequent root sprouts. water and a non-ionic below). Staghorn sumac leaves surfactant, is effective on do not have this gland, but Manual and Mechanical smaller trees when applied have toothed leaf margins, While young seedlings could between June and late August. while ailanthus’ leaf edges are be pulled or dug up, the smooth. Sumac fruits are chance of getting all root For larger trees, application of fuzzy and red. fragments is difficult and can triclopyr or glyphosate with

lead to re-sprouts. Seedlings the basal bark, hack and squirt, or injection should can be confused with root

suckers, which would be near- work effectively. Cut-stump

ly impossible to remove effec- herbicide application, howev-

tively by hand. er, may encourage root sucker-

www.invasive.org ing. Application rates may Cutting is not recommended, vary—see the references be-

Service, Service, as the trees will send up large low for more specific

Photo: James Miller, USDA Forest Forest USDA Miller, James Photo: numbers of root sprouts and information. Follow-up moni- suckers, creating a bigger toring and treatment are very problem than before. important. Regardless of the Young ailanthus may also be control method used, treated confused with black walnut areas should be checked one (Juglans nigra) because of the or more times a year. compound leaves and shield- shaped leaf scars. However, the flowers, seeds and smell of References: ailanthus should give it away. Plant Conservation Alliance’s Least Wanted List: Staghorn Sumac http://www.nps.gov/plants/alien/fact/aial1.htm

Center for Invasive Species and Ecosystem Health: http://www.invasive.org/browse/subinfo.cfm?sub=3003

Virginia Cooperative Extension: http://pubs.ext.vt.edu/420/420-322/420-322_pdf.pdf

For More Information:

Penn State University Vegetation Management Publications: Photo: John Cardina, The Ohio State University, http://horticulture.psu.edu/research/labs/vegetative- www.forestryimages.org management/publications