There are plants that seem to love Arizona, grow easily and maybe grow too well. Then, when you decide to get rid of them, it’s a struggle to do so.
One of them is a tree called the Dalbergia sissoo, commonly known as Sissoo or Indian Rosewood. This is a tree many homeowners plant because it’s lush and fast-growing.
Sissoos can grow to 35 to 40 feet, providing lots of shade, but their vigorous root systems can invade underground irrigation lines, sidewalks, block walls and even lawns. The roots can take over a yard after only a few years.
Some homeowners complain about the many pods and leaves that drop off the tree, but its roots pose the biggest problem. Then when a decision is made to remove the tree, the real headaches begin.
“Although Dalbergia sissoo is not listed as an invasive species,” says John Eisenhower of Integrity Tree Service in Phoenix, “it is considered by many horticulturists to be a nuisance tree because of its aggressive rooting and sprouting.”
Homeowners often call our radio program to ask how they can stop the Sissoo roots and suckers from spreading in their yards. According to Eisenhower, most of the problems begin when homeowners decide they want to cut down a Sissoo.
“Usually when you cut down a tree, it will be gone, but not Sissoos. After the tree is cut down, they don’t just send up volumes of sprouts from the cut stump like some other trees do. They send up shoots from every root that remains in the soil, creating an unwanted forest of trees sometimes 100 feet from the stump,” he says.
If this happens to you, there are some steps you can take to control the roots and sprouts, according to Eisenhower. You start by cutting down the tree and leaving a stump that’s 18 to 24 inches tall. Then you drill holes into the outer sapwood ring on top of the stump and fill the holes with a contact herbicide. This will kill the stump and roots to a certain radius from the tree.
Additional stump treatments, plus spot spraying of new shoots, will then be needed over the next few months to achieve full control of sprouting. Due to the massive amount of root material that Sissoos generate and the corresponding high volume of chemicals required to kill them, some people choose to first dig out as many roots as possible before applying chemicals. Soil removal and replacement to the full depth of the deepest roots is another option.
Eisenhower added that the chemicals needed for stump, root and sprout treatments are not available over the counter and need to be applied by a licensed applicator with the Arizona Office of Pest Management.
Despite the risk that aggressive rooting trees like Sissoos present, they remain very popular. If they have adequate room to grow where they will not encroach on surrounding landscape elements, they can be a beautiful and serviceable evergreen shade tree. It’s not that these are always bad trees; they’re just the wrong trees when planted in the wrong place.
Another plant that can refuse to die is Cat’s Claw. Homeowners often plant this drought-tolerant vine to cover up walls and fences. It’s hardy, loves the sun and gets yellow trumpet-shaped flowers in the spring. It can reach 25 feet high and 25 feet wide.
But as I know from personal experience, once you plant it, you might have it forever. In fact, if you want to get rid of it to make it easier to paint your walls or a fence, you should use the same method of killing it as is recommended with the Sissoo tree. It’s not impossible to get rid of Cat’s Claw. It just takes a long time.
For more do-it-yourself tips, go to rosieonthehouse.com. An Arizona home building and remodeling industry expert for 25 years, Rosie Romero is the host of the syndicated Saturday morning Rosie on the House radio program, heard locally from 8-11 a.m. on KNST-AM (790) in Tucson and KGVY-AM (1080) and -FM (100.7) in Green Valley. Call 888-767-4348.