How to eliminate tree root sprouts

Question

Location: Scottsdale, AZ.

As you will see in the attached photos, I have a tree (maybe some type of palo verde) growing out of a rock cropping. The roots that wind their way through the rocks are continuously issuing sprouts. These outgrowths are heavily laden with needle-like spines/thorns. How do I safely eliminate tree root sprouts (or, at least, retard the growth)?

I have cut the sprouts back as close to the the root as I can and sprayed the area with wound dressing. This just seems to encourage faster and more abundant sprout growth.

All help appreciated.

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Answer 1

It does look like a palo verde, and these trees can show invasive behaviors and spread from the roots (probably part of a desert survival strategy). If you can somehow cover the area where they sprout with an opaque covering to shut out light, the shoots should at least stop growing, and hopefully the roots will eventually decide that area isn't a promising direction to grow in.

These articles are about other types of trees but may help:
http://diagnostics.montana.edu/plant/topics/treeshoots.html
https://www.gardeningknowhow.com/ornamental/trees/tgen/tree-sucker-removal-and-tree-sucker-control.htm