Controlling tree of heaven requires systemic herbicide timed for late summer when carbohydrates flow to roots — cutting alone triggers aggressive resprouting from stumps and root fragments.
For the full breakdown, see our best Herbicide For Tree Of Heaven guide.
How to control tree of heaven comes down to one non‑negotiable rule: use systemic herbicide in late summer, or this invasive tree keeps coming back. Tree of heaven (Ailanthus altissima) resprouts aggressively from stumps and root fragments when cut alone, so an integrated approach with herbicide timed to the tree’s natural growth cycle is the only reliable way to eliminate it from your property. The key is matching your method to the tree’s size, the site conditions, and the season.
Why Does Late Summer Matter for Treatment?
Tree of heaven moves carbohydrates from its leaves down to its root system in late summer — typically after July 1 and before the tree shows fall color. Systemic herbicides hitched to that downward flow travel to the roots, killing the whole plant instead of just the top growth. Treating earlier in the growing season or after leaves change color misses this translocation window, and the tree survives to resprout from the root system. The effective window runs roughly from mid‑July through mid‑October, depending on your region and local climate. This single timing decision makes the difference between one‑and‑done control and years of repeated battles.
The Four Treatment Methods That Work
Choose your method based on tree size, stem diameter, and proximity to desirable plants or water. Each method uses the same timing principle — apply after mid‑summer when the tree is translocating carbohydrates to its roots.
| Method | Best For | Key Steps |
|---|---|---|
| Foliar Spray | Small to medium trees, large thickets where full leaf coverage is possible | Spray leaves thoroughly with a systemic mix (glyphosate plus triclopyr is a common choice) when the tree is in full leaf and before any fall color appears. |
| Basal Bark | Stems under 6 inches in diameter, no leaves within reach | Apply a 25% triclopyr ester plus 75% horticultural oil mix to the lower 12–18 inches of the trunk. Skip application above 85°F to avoid volatilization damage. |
| Hack‑and‑Squirt (Frill) | Stems over 6 inches in diameter | Make downward or angled cuts around the trunk — one cut per inch of diameter, minimum two — leaving uncut bark between cuts. Immediately apply a 50% triclopyr solution into each cut. |
| Cut‑Stump | Any size, best when the tree must be removed immediately | Cut the tree and brush triclopyr directly onto the fresh stump surface within minutes. |
For seedlings and small plants, hand‑pull or dig when the soil is moist, removing the entire root system — even small root fragments can resprout. Mowing or cutting alone will not kill established trees and typically worsens the problem by triggering dense resprouts from the stump and lateral roots.
Common Mistakes That Keep Tree of Heaven Coming Back
Even with the right herbicide and timing, a few errors let this invasive tree survive. The most frequent: cutting the tree first and expecting it to die on its own, treating before full leaf‑out or after fall color, using too little herbicide on the stump or in the cuts, fully girdling the trunk in hack‑and‑squirt applications (the uncut bark is essential for moving herbicide down to the root system), and skipping follow‑up monitoring. Plan to inspect treated areas for at least two years and re‑treat any resprouts or new seedlings promptly.
Always follow the herbicide label for exact rates, site restrictions, and personal protective equipment. Avoid foliar spraying on windy days or when herbicide could drift onto desirable plants. For basal bark treatments, skip days over 85°F to keep the oil‑herbicide mix from volatilizing. Penn State Extension’s tree of heaven control guide provides detailed application rates and regional timing advice for each method.
FAQs
Can you kill tree of heaven just by cutting it down?
Cutting alone usually fails because tree of heaven resprouts vigorously from the stump and from root fragments in the soil. The most effective approach is to treat the standing tree with a hack‑and‑squirt method, or cut it and immediately treat the stump with a systemic herbicide like triclopyr.
What herbicide works best on tree of heaven?
Systemic herbicides containing triclopyr, glyphosate, imazapyr, or dicamba are all effective when applied in late summer during the carbohydrate translocation window. Triclopyr is the most versatile option — it works for basal bark, hack‑and‑squirt, and cut‑stump methods across a range of stem sizes.
How long does it take for tree of heaven to die after treatment?
Treated trees typically show signs of decline within a few weeks to a few months, especially when systemic herbicide is applied during the late‑summer translocation window. Monitor treated areas for at least two full growing seasons and re‑treat any surviving resprouts or new seedlings promptly.
References & Sources
- Penn State Extension. “Tree of Heaven.” ID and control strategies for Ailanthus altissima in Pennsylvania landscapes.