Egg -The eggs are small and cream colored.
Pupa, Larva -The pupal and larval stages have not been described.
Host Plants -Some of the plants attacked by the Japanese weevil are ash, azalea, barberry, burr marigold, camellia, dogwood, elm, fern, hemlock, holly, lilac, mountain laurel, privet, rhododendron, rose, spirea, strawberry, and weigela.
Damage -Japanese weevil larvae feed on plant roots, but the adults do more serious and apparent damage. The weevils feed extensively on new leaves, shoots, and inner foliage. As a result, infested plants are tattered and unhealthy in appearance.
Life History -It is assumed that the Japanese weevil is parthenogenetic because no males have been recorded. Eggs are deposited in folds along the margins of leaf fragments or dead leaves, and the free edge is sealed to form a pod. When the eggs hatch, the larvae burrow into the ground and feed on the roots. These weevils have fused elytra and thus are unable to fly. They feed during the day and, if disturbed, drop to the ground and remain motionless. There is only one generation each year.
For specific chemical controls, see the current state extension service recommendations.
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