Facts, Identification & Control
Leaf-footed bugs are members of the Coreidae family of insects known for the small, leaf-like enlargements found on their hind legs. There are 11 species of the typical leaf-footed bugs in North America including the western conifer seed bug, which is common in Canada. Leaf-footed bugs are closely related to stink bugs and use their sucking mouthparts to extract juices from various plants.
Growing as large as 20 mm in length, most leaf-footed bugs appear brown in colour. The upper abdomen appears yellow or light orange and includes five crisscross black patches, which are generally revealed when the insect takes flight. Adults resemble bumble bees while flying due to their similar flight patterns and the loud buzz produced by both types of insects. Nymphs appear orange but slowly change to the colour of the adults after several moults.
Leaf-footed bugs are overwintering species which live in a variety of different environments but prefer well-protected areas. This may include woodpiles, under peeling bark, in tree cracks, and, depending on the region, palm fronds, citrus trees, and inside various manmade structures.
Different species tend to eat from different food sources, though all leaf-footed bugs typically feed on the seeds and fruits of various plants. The pest species has been known to feed on items ranging from tomatoes and pomegranates to numerous nuts, citrus fruits, and ornamental trees and shrubs.
Life Cycle / Reproduction
The eggs of the leaf-footed bug hatch after about 10 days, and females can lay up to 200 eggs at a time. Shaped like barrels, the eggs are deposited in rows, either on twigs or the leaves of plants. Typically, only one generation hatches each year. The insects go through five instars, or moults, before reaching full adulthood in about 30 days.
Problems Caused by Leaf-Footed Bug
Leaf-footed bugs seek shelter to overwinter, which leads to their occasional occurrence indoors when the weather begins to cool. As they aggregate in large numbers, they often alarm people with their increased activity and conspicuous arrival indoors at the end of the fall.
Additionally, leaf-footed bugs can damage crops as they feed. They excrete a digestive enzyme from their piercing mouthparts as a way of liquefying the seed or fruit for consumption. In doing so, they also release a fungal yeast that causes unsightly discolouration.
Detection / Signs of Infestation
The most common sign of a leaf-footed bug infestation is the sight of the insects during their attempts at overwintering. As leaf-footed bugs amass in large numbers, finding them on walls, windows, and in barns and other manmade structures is highly possible. Farmers, gardeners, and nursery attendants may notice shrivelled, deformed, or shrunken seeds where the insects feed. The pests can also affect different crops depending on how early the feeding occurs in the plant’s growth, leading to severe deformities and dead leaves.
The best ways to prevent leaf-footed bugs from entering indoors to overwinter are exclusion and removal of potential overwintering areas around the home, such as woodpiles, outbuildings, and high weed areas. Shield plants with row covers, which are made from a light, permeable material like polypropylene, to protect the vegetation from attack. Replace or repair any loose or damaged screens around the home, caulk around door and window frames, and seal any other possible points of entry, such as cracks in the foundation.
When leaf-footed bugs appear inside the home, use a vacuum to sweep them up. If the infestation becomes too large to handle, contacting a pest control professional may prove necessary. Trained pest control specialists know how to eliminate leaf-footed bugs completely and can also set up integrated pest management plans to keep the insects from returning.
Western Conifer Seed Bugs