Cranberry rootworm beetles, Rhadopterus picipes, are little (about 1/5 inch long) and lustrous brown.
In the immature stage, Cranberry rootworms are little, yellowish-white, slightly curled grubs with light brown heads and short legs. These rootworms spend the winter underground.
Puppies are born in April and May, and the new adults emerge in early June and remain active until the end of July. After about 2 weeks of eating, the beetles marry, and the females go under leaf litter to lay eggs.
The adults are unique because they eat mostly at night on the environment’s new growth of diverse bushes. They chew holes that are thin, straight, or crescent-shaped.
Host plant:
Cranberry rootworm beetles feed on camellia, photinia, rhododendron, and other shrubs and trees in the landscape, as well as cranberry leaves and fruit. Magnolias, hollies, oaks, roses, silver maple, sycamore, sumac, sassafras, and Virginia creeper are also consumed. As we can see, the microscopic rootworms feed on the bark of the roots of blueberry, cranberry, and maybe other plants.
Damages caused by Cranberry Rootworm:
These beetles are rarely spotted because they hide in the landscaping mulch during the day, and the foliar damage looks similar to hail damage. The adults eat on landscaping plants for many weeks in late spring and early summer. Their feeding causes curved, C-shaped, and elongated holes in azalea, rhododendron, camellia, blueberry, hollies, roses, redbud, oakleaf hydrangea, and other shrub leaves. Female adults deposit eggs on the earth after eating. Young beetle larvae go into the soil after hatching to feed on the host plant’s roots. They graze throughout summer until October, when they migrate deeper into the ground to overwinter.
Life history and Habits:
Females lay up to 150 eggs in groupings of 12 to 102 under dead leaves on the soil surface in July. The tiny immature grubs burrow down and begin feasting on roots 9 to 11 days after hatching. Feeding continues until October when the fares are approximately 5/16 inches long. Cranberry Rootworm have one generation per year
