Q. Is anything that can be done about cottonwood suckering from the roots after you cut the tree down, I poured stump killer onto it only to find later little cottonwood trees sprouting up around the stump and the lawn. A local expert said to pull out the sprouts until they start to go away.
A. The basic idea of exhausting the root system by removing the suckers is correct. Nearly all of the poplars, including cottonwood, sucker from the roots when they are cut down.
The mature tree acts like an energy sink for new growth. As long as the mother tree is alive, healthy and growing, it helps suppress growth from the roots. Once the mother tree is removed, the suppression of sucker growth is also removed. Suckers begin to grow from the roots as a survival mechanism for the tree.
These suckers will not pull easily because they are coming from roots. The usual term by “know-it-alls” is to "exhaust" the energy reserves in the roots by constantly removing sucker growth.
|Lawn dandelion killer containing dicamba in the ingredients|
The tree "invests" stored energy into sucker growth in a last ditch attempt to survive after it is cut down. In Mother Nature, this usually works. In a home situation with a diligent homeowner, removal of these suckers slowly but surely, exhausts the energy supply in the roots until finally the entire tree, roots and all, expires.
What to do? Remove the suckers as soon as you see them. This is no easy task even for the young at heart. Chemicals can help us remove or kill new sucker growth. By spending some money and purchasing products such as Glyphosate or a dandelion killer that contains dicamba or triclopyr in the ingredients makes this job much easier.
|I have been quite happy with my red Dragon flame weeder that is worked quite well|
If a lawn is present, dandelion killer that will also kill clover or tough to control lawn weeds would be a better choice than Glyphosate. If this is a desert landscape with rock mulch everywhere, then Glyphosate would be a good and possibly better choice.
Another possibility is to use a propane flame weeder such as Red Dragon. It will not work in a lawn very well but in a desert landscape it works quite well to burn down sprouts rather than to kill them with chemicals.
Spraying must be done when the sprouts are still young and immature to get good kill. They have to stay on top of this sucker growth and not let it get out of hand and spray probably once a month during the growing season as soon as new growth appears.