Weeping Willow Tree
With a pool in the yard

Q: Hi, I planted a 6 foot (at the time) weeping willow tree in my backyard 5 years ago. Both my yard and my neighbors have in-ground pools.

My neighbor tells me that Willows seek water and the roots will eventually find the pool lines and crush them. Is this true and how old would the tree need to be to accomplish this if so.

Thanks so much, Lou

A: Tree roots grow in response to what they find where they find it as they grow along. In other words, roots are not able to go "searching" for water and nutrients if the conditions along the way are not conducive to root growth. If, for instance, the ground is too dry and lacks sufficient nutrients, roots will not continue to grow there.

Since roots do grow "seeking" water and nutrients as the conditions allow, it is possible that they will eventually make their way to near your pools and the water lines. However, roots do not "crush" water lines like a boa constrictor kills its prey, so there is little risk of damage along these lines.

If you are still worried, you can impede root growth by installing a root barrier between the tree and the pools. There are a number of ways to do this, including installing special root barriers that have an herbicide impregnated into them.

As the root tips encounter the barrier, a small amount of herbicide is released, killing the root tip. Check with your local nursery or garden center for this or other root barrier products.