Tree of Heaven – Invasive Plant
The Tree of Heaven plant, Ailanthus Altissima, is undoubtable beautiful, and thrives in Peachland, but
DID YOU KNOW it is an
INVASIVE PLANT?
What makes Tree of Heaven Invasive?
- It grows rapidly and produces large quantities of seeds that can be wind-dispersed, allowing the tree to establish in new areas quickly.
- It releases chemicals from its roots that inhibit the growth of surrounding plants, making it difficult for native species to thrive near them.
- It has an aggressive root system, sprouting new shoots from roots even after the tree is cut down.
- It is extremely tolerant of a variety of environmental conditions, thriving with little water in areas with poor soil or pollution and in urban environments like roadsides, vacant lots and pavement cracks.
- Outside of its native range, China and Taiwan, the Tree of Heaven faces few natural predators, diseases, or pests.
These traits mean the Tree of Heaven can outcompete native plants, reduce biodiversity, and alter habitats, making it a particularly problematic invasive species in many parts of the world, especially in North America and Europe.
It also produces a lot of pollen which can cause allergies, and its leaves, branches, seeds and bark can irritate the skin. It is also the main host of the spotted lanternfly, which hasn’t been seen in the Central Okanagan, but the fruit industry is watching as the invasive species which feeds on a variety of agricultural crops, has been detected in several United States and Ontario.
How Can You Identify Tree of Heaven?
Leaves
- Long, compound leaves ranging from 1 to 4 feet in length, 10 to 40 leaflets per leaf.
- Lance-shaped leaflets with smooth edges (no teeth or serrated edges) except for 1 to 2 small notches near the base.
- When crushed, the leaves emit a bad odor compared to burnt peanut butter or rancid nuts.
Bark
- Smooth and light grey or greyish brown when young and, as the tree ages, may develop more pronounced ridges and become somewhat rougher.
- Striped appearance, some describe as having a pattern that looks like cantaloupe skin, especially on younger stems
Flowers
- Small clusters of yellowish-green flowers in late spring or early summer, growing in large loose panicles and are not particularly showy.
- Male flowers give off a strong, unpleasant odor.
Seeds
- The tree produces reddish-brown to tan samaras (helicopter seeds) with a winged structure allowing them to disperse by wind.
Growth Form
- The plant is fast growing, up to 80 feet tall, and often has an unkempt, scraggly appearance.
- It frequently sends suckers from the roots which can form dense clusters of young trees around a larger parent tree.
Environment
- Commonly found in urban areas, roadsides and disturbed landscapes due to its ability to grow in poor soil conditions.
- Also common along riverbanks and in forests.
How can you get rid of Tree of Heaven?
Take these steps to permanently remove Tree of Heaven plants from your property.
1. Cut the tree at its base, close to the ground and immediately apply an appropriate herbicide to the freshly cut stump to prevent regrowth. For larger trees, use the Hack and Squirt method; make downward cuts into the trunk of the tree and apply herbicide directly into the cuts. Note: herbicidal treatments work best from late summer to early fall when the tree is sending nutrients to its roots.
2. After the main plant is removed, you need to dig up the roots as this is how the Tree of Heaven spreads. Repeated mowing or cutting of suckers can weaken the tree over time but without herbicide this may require constant monitoring and removal for several seasons.
3. Properly dispose of the removed plant material; it can sometimes regrow from cuttings. Do not leave cut material in contact with the soil.
4. Monitor the area for at least a few years as new seedlings and root sprouts can appear.