What Do Hissing Beetles Eat?

Hissing beetles, scientific name Polyphylla decemlineata, belong to the scarab beetle family. In addition to the unusual hissing made when bothered, their white striped shells earn them another name: tenlined June beetle. These beetles live west of the Rocky Mountains in the United States and in Canada. Unfortunately, other than their white stripes and hissing noises, not much else about finding this pest gives most people a reason to celebrate.

  1. Food

    • All stages of the beetle feed on plants. Common trees include Douglas firs and other firs, pines, apple and other fruit trees. The hissing beetle also attacks strawberries, almonds, potato, corn and roses. The tenlined June beetle feeding causes the most destruction, with up to 30 percent of young forest trees lost in some areas of British Columbia, according to the Canadian Forest Service.

    Larvae

    • The tenlined June beetle begins causing destruction in the larval stage, injuring and killing trees and other plants by damaging the roots, according to the University of California Integrated Pest Management Program. The C-shaped larvae, which take two to four years to mature, live underground feeding on tender roots and decayed plant material. Young trees grown in sandy soil where sagebrush grew may become a food source for waiting hissing beetle larvae.

    Older Grub

    • As the larvae grow, they move closer to the surface to feed on the woody roots of the plants or trees. The damage done by the older grubs, generally about 1 foot beneath the soil's surface, causes the most destruction to the hosts. The feeding on that part of the root may cut the roots off at a shallow level, making it possible to easily pull the plant or tree from the ground. The grubs may also feed on grasses. Often you only know if your trees became part of the beetle's menu when trees begin dying, according to University of California Integrated Pest Management Program.

    Adults

    • The adult hissing beetle bores out of the ground after the pupal stage to find food above ground. It often feeds at night on the leaves of different fruit, broadleaf and conifer trees and plants. The adult hissing beetles' feeding causes minimal damage, according to the Canadian Forest Service.

    Usefulness

    • Although the hissing beetle creates damage from eating roots, other creatures make use of the beetle. Grubs make a meal for birds and a host for the tiphiid wasp larvae. Bats and owls consume the adult hissing beetle and the flesh fly uses them to deposit its larvae.