Ailanthus altissima, more commonly known as Tree-of-Heaven, is an invasive species growing across the United States. This deciduous tree is native to Asia, originating from both China and Taiwan. Valued for its ability to thrive in poor conditions, this fast growing tree, planted extensively along the east coast of the United States in the 1700’s, began losing popularity by the early 1900’s. What was once seen as a prolific ornamental shade tree was then viewed as a weedy tree with a distinct smell.
This invasive is commonly found along road sides, riverbanks, and it even pops up here at Wellfield Botanic Gardens! Ailanthus altissima can reach up to 80 feet tall, with a brown/gray trunk that turns to a solid gray once matured. A. altissima blooms in late May to early June with green/yellow flowers. The leaves of this tree are pinnately compound and are often mistaken for Staghorn sumac (Rhus typhina). Tree-of-Heaven have smooth leaves, while Sumac are serrated.
A good way to distinguish between both is by crushing the leaves, as A. altissima has a distinct odor. The seeds on A. altissima are samaras, similar to the seeds on maple trees, however the seeds on this invasive are twisted and found in clusters.
Pictured above is Tree-of-Heaven featuring its twisted samaras.
Since this species can thrive in just about any conditions, they can often take over an area and choke out native species. A. altissima release allelopathic chemicals from its roots, bark, and leaves, and can prevent other plants from growing in the area surrounding this invasive. To combat the spread of A. altissima, herbicide can be applied to the roots. Pulling can work with saplings, however, roots can be extensive and pulling may leave behind some roots.
At Wellfield Botanic Gardens, because we are the City of Elkhart’s working well field, we are limited in what chemicals we can apply to our soils. We try to combat this invasive by pulling young saplings. While we don’t have any growing in the Gardens, they can be spotted in the area surrounding the Gardens. Now that you can identify this tree, check your yard and do your best to protect native wildlife!
Ariana Guerrero Horticulturist
#EDUCATION #gardening #invasivespecies #trees #horticulturetips #wellfieldbotanicgardens #permaculture #wellfield #horticulture #landscaping
