Question
We have Sumac that spread up a hill and is now 3 meters away from our vegetable garden. Lately new Sumac shoots appeared among the vegetables.
How can we keep the Sumac out and from spreading further.

Answer
Frank, the short answer is that it is very tough to kee them out. you can keep cutting them down, but new ones will try and grow again. What you may try is to cut down at the edge of the garden, and use some steel edging. the steel edging is only about 4" thick, and you will want that right to the surface of the soil. this may help, but probably wont stop them totally. you can also try timbers, and put them in say 1 foot down, along the edge of the garde (use two 5x6 treated timbers, and dig them both in so they are burried. this would probably help the most. the only other solution that I know of would be to kill off the sumac, something I would not be a big fan of, and may be more trouble than putting in timbers. Good luck.

Mark