Tree of Heaven is a invasive species that can be difficult to control. Herbicides applied in late summer or fall after the sap has flowed down are most effective for killing the roots. Two recommended techniques are hack-and-squirt and cut stump. For hack-and-squirt, cuts are made into the inner bark and herbicide foam is inserted. For cut stump, the tree is cut down leaving a 2-5 inch stump and herbicide foam is applied to the exposed phloem. Both techniques require leaving the stump undisturbed for 6 weeks to ensure the herbicide kills the roots.

1. Tree of
Heaven Control
using Foam
Herbicide
By: John Lampe
January 30, 2014

2. Never cut tree of heaven down without an
herbicide treatment.

3. It will sprout vigorously making it even harder to
control.

4. Don’t apply herbicide
in Spring or Early Summer
to Tree of Heaven

5. Spring and early summer – sap flowing up, and
systemic herbicides cannot easily reach roots.

6. Do apply herbicide
in Late Summer or Fall
to Tree of Heaven

7. Late summer and fall – sap flowing down and
systemic herbicides can reach roots.

8. Two good techniques:
• Hack-and-squirt
• Cut stump

9. First technique
hack-and-squirt

10. Recommended Herbicides for hackand-squirt:
• Glyphosate (trade names: Roundup®, Killzall,
and others)
• Imazapyr (not typically sold in consumer sizes)
• See DiTimaso et al. 2007.

11. Read the herbicide
label before starting.

12. Hack and
Squirt
Treatment
Use hatchet or machete.

13. Make series of cuts into live inner bark.

14. Place cuts around circumference of tree.

15. For thin barked trees, you may instead use a
wood chisel . . .

16. to make cuts around circumference of tree.

17. 2 to 5 inches
Above the ground.
Make cuts about 2 to 5 inches above ground.

18. ½ to 1 inch spacing
between cuts
Make cuts about ½ to 1 inch apart.

19. Apply foam herbicide within 5 to 10 minutes of
making cuts.

20. Fill each cut with foam herbicide.

21. Make sure herbicide contacts live tissue of inner
bark.

22. To ensure root kill, don’t cut or otherwise
disturb tree for at least 6 weeks.

23. Second technique
cut stump

24. Recommended Herbicides for cut
stump:
• Triclopyr (trade names: Garlon®, Brush b gon®
and others)
• Imazapyr (not typically sold in consumer sizes)
• See DiTimaso et al. 2007.

25. Cut stump works well for any tree that you feel
capable of cutting down.

26. Use saw for larger trees or
loppers for smaller trees.

27. 2 to 5 inches
Above the ground.
Cut should leave a stump about 2 to 5 inches in
height.

28. Apply foam herbicide within 5 to 10 minutes of
making cuts.

29. Apply foam herbicide onto the phloem. . .

30. The phloem is the live, inner bark just inside the
rough outer bark.

31. Apply foam herbicide around circumference of
entire tree.

32. To ensure root kill, don’t grind out or otherwise
disturb stump for at least 6 weeks.

33. More Information
Green Shoots®: www.greenshootsonline.com
Contact: john@greenshootsonline.com
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