Can You Spray Roundup Around a Weeping Japanese Maple?

Learning About Laceleafs

• The term "var." in its scientific name means that the laceleaf Japanese maple is a variety, a naturally occurring mutation. Some common weeping cultivars are “Filigree” (Acer palmatum var. Dissectum “Filigree”), which has fine leaves that turn yellow in the fall; and “Garnet" (Acer palmatum var Dissectum “Garnet”), which has red to purple leaves that do not fade. You can grow laceleaf maples in U.S. Department of Agriculture plant hardiness zones 5 through 9.

Watch Those Flowing Branches

• Roundup is a systemic contact herbicide, meaning that it enters the plant through contact with green tissue, including the stems of perennial plants and the leaves of weeping maples. It moves from the foliage through the rest of the plant. If you spray Roundup close to a weeping maple, you risk getting it on the shrub’s flowing branches. As an alternative to spraying, daub Roundup on individual weeds. Roundup is highly adsorbed by most soils, meaning its molecules bond to molecules in the soil and does not move. Its half-life in soil, the time it takes for half of it to break down in the soil, ranges from one to 174 days. Since it does not move through the soil, it will not move into the roots of weeping maple.

And Don't Kill the Fish

• Roundup and Roundup Pro both contain surfactants that help the herbicide cling to plant leaves so that the glysophate can penetrate the plant tissue. The surfactants in Roundup and Roundup Pro are made from sheep or cattle fat. Roundup containing surfactants will kill salamanders, frogs and fish. If your laceleaf Japanese maple is near a fishpond, use a Roundup acquatic or wetland formulation that does not contain surfactants.

Be Careful!

• Do not store, mix or apply Roundup in unlined steel or galvanized steel containers or spray tanks. If you do, it can form highly combustible hydrogen gas that a cigarette or spark can cause to flash or explode. Wear socks, long pants, long-sleeved shirts, and goggles or other protective eyewear when you apply it. Wash your hands thoroughly after you apply Roundup and discard any clothing that has been drenched with it.