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Western Boxelder Bug – Boisea rubrolineata

Western Boxelder Bug: Appearance, Territory, Damage and Life Cycle

Latin Name: Boisea Rubrolineata Appearance: The western boxelder insect is a common pest in and near dwellings. Boxelder bugs mostly feed on the leaves, flowers, and seedpods of female or seedbearing box elder trees, however they may also feed on male box elder trees and, on rare occasions, maple and ash trees. They can eat the fruits of almond, apple, cherry, peach, pear, and plum trees, as well as grapes, where their feeding punctures cause the fruit to distort. Large populations of the insect are generally found solely on female box elder trees. Hosts Plants: Other host plants include maples and ash. Feeding may also occur on agriculturally important plants like as fruit and nut trees, grapes, and strawberries. Western boxelder insect feeding can cause crop damage to fruit trees, pistachios, and almonds. Territory: The western boxelder insect is found in British Columbia, Canada, as well as in California, Nevada, Utah, and Texas. These insects are part of the Rhopalidae family, which includes scentless plant bugs. Damage Insect Cause: Ornamental trees are not harmed by the pests. They may cause puckering or deformation of fruit in commercial orchards such as pear or kiwi on occasion, although this is seldom a serious issue. They do not harm humans or pets, but when they come indoors, they may be bothersome since their feces can stain drapes, furniture, and clothing. When crushed, they emit an unpleasant stench. They do not reproduce inside. They will perish if they are confined in basements or houses. Life History and Habits: Overwintering female bugs deposit eggs in the cracks and crevices of the box elder tree’s bark in the spring, and the nymphs hatch in a few days. During the summer, the nymphs grow bigger and mature into adults. They then mate and lay eggs, which hatch into nymphs of the next generation. Adults and nymphs move in huge groups on a regular basis, often covering tree trunks, the ground, fences, and the sides of homes. The majority of the second-generation nymphs reach full size between August and September. Adults seek overwintering sites in dry, protected hollow tree trunks in the fall. When they enter in large numbers, they create a nuisance both outside on patios and indoors. Boxelder bugs can be seen relaxing in the sun on light painted surfaces outdoors on the south and west sides of the home on warm days in winter and early spring.