Question
I have a crabapple tree in a well maintained front lawn.
The problem is that root suckers, probably 100 of them,
keep growing through the grass and mulch bed tthat surround the tree.  How do you kill these things. If you apply too much Roundup, the tree will die, because these are actually roots of the tree as you know.  I read about a product called sucker stopper on the internet.  Have you heard abouyt these?  Currently, I just weed whack these suckers off every week.

Answer
I have heard of the sucker stopper but have no experience with it. I would use it it could save you the time cutting back the suckers. I would not use Roundup since the herbicide will move into the tree and kill the root system. Check with your local nursery and ask them to order the sucker stopper if they do not care it. Here is the web site for the product. http://www.montereylawngarden.com/faqs/suckerstopper/