Aggressive root system, wood is weak and breaks easily, and infestations crowd out native tree species
The Tree of Heaven (Ailanthus altissima) is one of the most controversial trees in North America. Originally introduced from China in the late 1700s as an ornamental shade tree, it has since become an aggressive invasive species in many states, including parts of Colorado.
While it does have a few positive traits, its drawbacks far outweigh its benefits for most landscapes.
The Good
Fast Growth - Tree of Heaven grows remarkably quickly, often 3 to 6 feet per year when young. It can provide shade in a relatively short time.
Tough and Adaptable - it tolerates:
This ability allows it to survive where many other trees struggle.
Erosion Control
Because it grows rapidly and develops an extensive root system, it can temporarily stabilize disturbed soils on slopes and abandoned sites.
The Bad
Highly Invasive
Tree of Heaven spreads aggressively by both seeds and root suckers. A single female tree can produce tens of thousands of winged seeds each year, and roots can send up new shoots many feet from the original tree.
Difficult to Eliminate but don't simply cut it down!
Simply cutting the tree down usually makes the problem worse because the roots respond by producing numerous new sprouts. Effective control often requires a combination of herbicide treatments (Triclopyr works best) and follow-up removal.
Crowds Out Native Plants
Dense stands of Tree of Heaven shade out native grasses, shrubs, and wildflowers, reducing biodiversity.
Strong Odor
The leaves, flowers, and crushed stems produce a distinctive odor that many people describe as similar to rancid peanut butter, burnt rubber, or unpleasant chemicals.
Weak Wood
Branches can become brittle and are prone to breaking during heavy snow, ice, or windstorms.
Attracts the Spotted Lanternfly
Tree of Heaven is a preferred host for the invasive Spotted Lanternfly, an insect that feeds on many economically important plants. Although the lanternfly is not yet widely established in Colorado, reducing Tree of Heaven populations can help limit suitable habitat if the insect spreads.
In Colorado, Tree of Heaven is found in many Colorado communities, particularly along:
Our dry climate slows its spread somewhat compared to wetter regions, but it is still considered an undesirable invasive tree in much of the state.
Should You Plant One? For most Colorado homeowners, no. There are many better choices that provide shade and wildlife value without the invasive risks. Some excellent alternatives include:
Tree of Heaven earned its reputation because it is fast-growing, drought tolerant, and nearly impossible to kill, but those same qualities make it one of the most troublesome invasive trees.
If you already have one on your property, it's generally best to manage or remove it before it spreads further. If you're looking for a new shade tree in Colorado, choosing a well-adapted native or non-invasive species will provide longer-lasting benefits for your landscape and local wildlife.
Colorado Department of Agriculture article and fact sheet
While it does have a few positive traits, its drawbacks far outweigh its benefits for most landscapes.
The Good
Fast Growth - Tree of Heaven grows remarkably quickly, often 3 to 6 feet per year when young. It can provide shade in a relatively short time.
Tough and Adaptable - it tolerates:
- Poor, rocky soils
- Drought
- Air pollution
- Road salt
- Compacted urban soils
This ability allows it to survive where many other trees struggle.
Erosion Control
Because it grows rapidly and develops an extensive root system, it can temporarily stabilize disturbed soils on slopes and abandoned sites.
The Bad
Highly Invasive
Tree of Heaven spreads aggressively by both seeds and root suckers. A single female tree can produce tens of thousands of winged seeds each year, and roots can send up new shoots many feet from the original tree.
Difficult to Eliminate but don't simply cut it down!
Simply cutting the tree down usually makes the problem worse because the roots respond by producing numerous new sprouts. Effective control often requires a combination of herbicide treatments (Triclopyr works best) and follow-up removal.
Crowds Out Native Plants
Dense stands of Tree of Heaven shade out native grasses, shrubs, and wildflowers, reducing biodiversity.
Strong Odor
The leaves, flowers, and crushed stems produce a distinctive odor that many people describe as similar to rancid peanut butter, burnt rubber, or unpleasant chemicals.
Weak Wood
Branches can become brittle and are prone to breaking during heavy snow, ice, or windstorms.
Attracts the Spotted Lanternfly
Tree of Heaven is a preferred host for the invasive Spotted Lanternfly, an insect that feeds on many economically important plants. Although the lanternfly is not yet widely established in Colorado, reducing Tree of Heaven populations can help limit suitable habitat if the insect spreads.
In Colorado, Tree of Heaven is found in many Colorado communities, particularly along:
- Roadsides
- Railways
- Vacant lots
- Urban areas
- Irrigation ditches
- Disturbed landscapes
Our dry climate slows its spread somewhat compared to wetter regions, but it is still considered an undesirable invasive tree in much of the state.
Should You Plant One? For most Colorado homeowners, no. There are many better choices that provide shade and wildlife value without the invasive risks. Some excellent alternatives include:
- Bur Oak
- Kentucky Coffeetree
- Hackberry
- Honeylocust (thornless cultivars)
- Ponderosa Pine (where appropriate)
Tree of Heaven earned its reputation because it is fast-growing, drought tolerant, and nearly impossible to kill, but those same qualities make it one of the most troublesome invasive trees.
If you already have one on your property, it's generally best to manage or remove it before it spreads further. If you're looking for a new shade tree in Colorado, choosing a well-adapted native or non-invasive species will provide longer-lasting benefits for your landscape and local wildlife.
Colorado Department of Agriculture article and fact sheet