Are Red Maple Trees Resistant to Japanese Beetles?

Red Maple Susceptibility

• The red maple (Acer rubrum) is rarely damaged by the Japanese beetle. The insect also tends to avoid silver maple (Acer saccharinum) and boxelder (Acer negundo), although the latter may occasionally sustain light feeding courtesy of the bug. Plant red maples, in addition to a large number of other common trees and plants, in a landscape setting when populations of Japanese beetles are known to exist in an area.

Susceptible Species

• Species of maple most likely to face an onslaught from the Japanese beetle include the Japanese maple (Acer palmatum) and the Norway maple (Acer platanoides). The insect is also highly attracted to the Prunus species, which includes cherry, plum and peach trees, in addition to bushes like the Rose of Sharon (Hibiscus syriacus) and true rose (Rosa) species. A number of other common tree species like American elm, ash and chestnut provide a prime nesting habitat for the beetle.

Japanese Beetle Identification

• The adult Japanese beetle measures less than 1 inch in length and has a metallic green body with copper brown wings and tufts of white hair that jot out from beneath each wing. The insect forages on approximately 300 species of plants, devouring leaves, fruit and flowers. Congregating in groups, the beetles typically work their way down from the top of a tree or plant in late June. With a lifespan of 30 to 45 days, the beetles normally inflict the most intense damage before the end of August.

Beetle Control

• As they chew away leaf tissue, Japanese beetles give a tree a skeletonized, scorched appearance. Both adults and grubs cause damage, so control of one group does not necessarily minimize injury to the tree or plant. You can control an infestation on small bushes or plants by simply picking the beetle from the foliage and destroying it. A number of insecticides are effective in managing the Japanese beetle, as are some organic methods. However, the more culturally sensitive techniques must be repeated every few days in order to deter feeding.