Pests of the Redbud Tree

The redbud tree (Cercis canadensis) brings an abundance of small magenta blossoms on leafless branches to your landscape in early spring. After flowering, it produces small pods and green, heart-shaped leaves that add fall color to your yard with the first frost. Redbud trees thrive in full to partial shade. Growing from 10 to 35 feet tall, depending on the species. They attract pests such as caterpillars and scale insects. The Eastern redbud tree grows in United States Department of Agriculture plant hardiness zones 6 to 9, the Mexican redbud tree grows in zones 6B through 8, and the Western redbud tree grows in zones 6 through 9.

Red-humped Caterpillar

  1. The red-humped caterpillar (Schizura concinna) is about 1.5 inches long. This gaudy pest has a red head, a red bump behind its head, and a yellow body with red and white stripes. Red-humped caterpillars eat redbud leaves and lay egg clusters on the underside of the leaves. However, the tree's overall health is not usually at risk since the pests show up just before the leaves fall off. Control red-humped caterpillars without chemical pesticides by using several methods. For small trees, prune off the leaves with caterpillar eggs and pick off the caterpillars by hand. On larger trees, spray bacillus thurengensis, a natural microbial, or release parasitic wasps, including Cotesia, Apanteles and Hyposoter fugivitvus.

Tent Caterpillar

  1. The tent caterpillar (Malacosoma americanum) is easy to recognize with its furry, reddish-brown body, blue spots and tufts of white to orange hairs. You typically see tent caterpillars in large numbers munching on redbud foliage during the day and slithering around inside silken webbed nests from dusk until dawn. Uncontrolled tent caterpillar infestation can defoliate an entire tree. To control these pests, prune infested limbs from the tree or tear open the nest with a stick and spray bacillus thurengensis inside. As an additional measure, wrap sticky tape used for catching caterpillars around the trunk of the tree.

Scale Insects

  1. Redbud trees attract oleander scale (Aspidiotus nerii) and greedy scale (Hemiberlesia rapax), but these pests won't cause irreparable damage. In fact, even high populations of these specific scale species don't typically harm redbud trees. Adult scale insects are wingless, don't move and do not have a separate head or recognizable body parts. They have an oval or elongated shape that resembles a small round or flattened hump. As scales suck the juices out of the leaves, they exude honeydew that attracts ants. Control scale insects by releasing lacewings or ladybugs and spraying horticultural oils.

Leafcutter Bees

  1. Leafcutter bees (Megachile) cut away small semi-circular portions of leaves on redbud trees. This might look like the work of a pest, but leafcutter bees aren't pests at all. In fact, they are an important part of the ecosystem -- some people place wooden bee blocks out in the garden to attract them. Leafcutter bees pollinate flowers, so don’t try to get rid of them or spray them with pesticides. While these bees might aesthetically damage some of the redbud tree's leaves, they won't cause harm to the tree and do benefit the flowers in your garden.