I've grown some pigweed here and the leaves I'm told are edible. Some of it also has some nice sharp thorns and I've placed it in areas where I've seen squirrels digging holes. It seems to be working. I let one seed last year and they supposedly produce 200,000 or more seeds and I believe it. The seeds are supposedly viable for up to ten years, not that I care but from one plant I've already pulled up 20 (or more) pigweeds and have been using them here and there where I've seen squirrels digging. They've stopped digging in those areas.
Not all of it has thorns but most of it does. I basically pull all the leaves off and make sure there's no seeds on the stem before I drop the stem in the area where I don't want squirrels. The squirrels seem to have a very good memory and so far it's working very well.
If you've got another type of thorny vine, lay that around the area where your tomatos are growing.
-- Jim Carlock Please post replies to newsgroup.