Don’t Be Stumped by Runaway Roots

Question: We have a parkway tree that is lifting and destroying the sidewalk in front of our home. We realize we will need a city permit to do anything, but I wonder if you know of any companies that handle such problems. Ideally, we would like to cut the roots, install a root barrier and then repair the damaged concrete.

Answer: I checked with my neighbor, Lauren Melendrez, a partner in Carlson-Melendrez Associates, which does site planning and landscape architecture and often handles tree problems. Melendrez suggested we call the Los Angeles street tree division, Department of Public Works.

Robert W. Kennedy, superintendent of the division, said you should request that a street tree inspector to look at the tree. He pointed out that you must obtain from the division a root-trimming permit or a pruning permit before any of the work can be done. The sidewalk repair permit must be issued by the bureau of engineering, Department of Public Works.

The problem with having runaway roots trimmed is that it is almost always necessary to trim the top of the tree at the same time. This is to assure that you don’t end up with a top-heavy situation; that is, too much tree for too few roots.

Street tree division inspectors are able to advise how much a tree should be trimmed and recommend ways to find someone to do the root and tree trimming, Kennedy says, adding that some trees can be root-trimmed easier than others, depending upon the species.

Root barriers, plastic strips that are installed at ground level and extend into the earth 12 to 18 inches, are not panaceas, Kennedy says, but they do guide new root growth downward, rather than outward.

In past years, the street tree division handled root trimming at no charge, but today, according to Kennedy, the division does not have the personnel nor the equipment to provide that service.

The inspector who comes to your house will offer advise to you and/or your contractor on how the work should be done. Kennedy suggests that you get a minimum of three bids for the work and get a licensed contractor. And, as always, get the bid in writing.

To request the help of an inspector and apply for your permits, 200 N. Main, City Hall East, Room 1550 or call 213/485-5661.

Also, you can get the name of an arborist in your area through the National Society of Arboriculture. Send a self-addressed post card to Roger Garrigue, 1462 Thurlene Road, Glendale, Calif. 91206. He is secretary-treasurer of the Western chapter.

And L.A. County environmental horticulturist Don Hodel is available to offer advice. His office is at 2615 S. Grand Ave., Suite 400, Los Angeles 90007.