Persistent Tree Roots

by Don
(Waynesville, nc)

I have large fower beds, some have areas within 15-30 ft of some large 60 yr old maple trees. When tilling the soil 15 yrs ago, I was amazed at the matted fine hair roots. After a couple of years, they were back just as thick again. Needless to say, even some perennials have not done well in those areas. My method now to combat the roots is to dig up 4' x4' holes to a depth of about 20", line the entire hole, bottom and sides, with landscape mulch and refill hole with soil and lots of organic material. This seems to retard the roots for a few years, but eventually they start to creep back in. My question is - Is there any chemical or substance that could that could be put on the backside of the landscape cloth that would inhibit he growth of the tree roots back into the hole?

Doug says there are a lot of chemicals you can use to kill roots but none I'd recommend using - given that all are serious ground poisons and will pollute terribly. Anything you put down will migrate across to your perennial roots given the nature of water and material movement in soils. It's like putting creosote down and expecting nothing bad to happen to the soil or water there. For example, if you put down creosote to kill off tree roots - it will migrate into the perennial areas and kill off the perennial roots as well.

This is a problem of growing under trees in the shade and one we all deal with on a yearly basis. There is no "permanent" cure other than to cut down the trees.

Your own system is probably as good as you're going to get.