Re: What is this thorn bush?
Can you post a picture taken further back, showing more of the bush (and if possible, the leaves)? It looks like a Himalaya blackberry, but it's hard to tell by just looking at the canes. You can also bring a sample to your county Extension office (usually run by your state university) for identification and advice.
If that's what it is, there are two ways to get rid of them. The most environmentally friendly is to grub them out by the roots (you must remove the roots) but that will be a LOT of hard work.
You can also use an herbicide that is listed for the species of plant you want to remove and that is absorbed by the foliage, being careful not to get any on desirable plants (your trees). Crossbow is one such herbicide, but may require application by someone who is a certified applicator.
Even after application of herbicide, you may find that some of the plants will regrow from the roots. These root wads must be completely removed; if possible, destroy them by burning. Himalaya blackberry is a particularly tenacious, invasive species not native to the United States.
Last edited by Fencepost; 01-01-2011 at 04:00 PM.
The "Senior Member" designation under my name doesn't mean I know a lot, it just means I talk a lot.I've been a DIYer since I was 12 (thanks, Dad!). I have read several books on various home improvement topics. I do not have any current code books I can refer to. I was an apprentice plumber for two years.