Q. I have a maroon Japanese lace leaf maple. Its about 24″ high and about 40″ across. In the top middle branch I get green leaves that aren’t the same as the rest. Besides being green they don’t have the same pattern. WHY? Bob Hanna – Auburn, WA
A. Lace leaf maples are clonal cultivars of the Japanese Maple (Acer palmatum) selected for their interesting leaf shape and color. These clonal cultivars are commercially propagated by grafting cuttings onto common Japanese Maple (Acer palmatum) rootstock. Cuttings can also be rooted. It faster to graft them and the resulting plants are generally more vigorous and become saleable faster than rooted cuttings. Many laceleaf maples use what is called a “high-graft” so that the plants have a nice straight long trunk. This means that most of the trunk is the plain green Acer palmatum. Low-grafts on the other hand are usually closer to the soil line. When a graft is made of a cutting the top of the rootstock is left in place until the graft takes and then it is removed leaving only the laceleaf cultivar. Often the rootstock will attempt a “coup d’état” in the form of suckers. This is obvious in a low-graft plant since they look out of place growing from the base of the tree. But in a high-graft they are less obvious except in this case where there is an obvious difference in leaf shape and color between the rootstock and the graft. Follow the “offending” branch back to the trunk and remove it. Keep an eye out for future suckering of the rootstock so you can literally “nip it in the bud” (couldn’t you just image Kelsey Grammer as Frasier saying that?).