Rose chafers areÂ small beetles (8-12mm long) tan coloured with a reddish brown head. They have long spiny legs.Â
Rose Chafers-Cooper Seeds
Larvae are small and resemble white grubs. Eggs are shiny white and oval. Pupae are light brown and about 15mm long. They are more prevalent in sandier soils.
Lifecycle (left)-NC State University, Larvae (right)-Later’s
Habitat and Lifecycle
They occur in most of the USA except for the pacific states and in Eastern Canada. They overwinter as larvae and adults emerge in early may or june and begin to feed. They lay their eggs in sandy areas and grasslands. Eggs are laid in groups of up to 40 but individually and not in clusters. When larvae emerge they feed on roots of hosts.
Damage-Michigan State University
Diet and Damage
They attack not only roses but dahlias, peonies, carnations, geraniums, apples, peaches, grapes, wisteria, delphiniums, elm and many more ornamentals. They are voracious in great numbers. They eat the flowers and leaves of hosts. Damage consists of skeletonized leaves, defoliation and flower drop. Nymphs eat the roots of plants. These are extremely destructive to any plant or root.
1) Hand Pick
Whenever you see them destroy immediately. These bugs are poisonous to chickens and livestock so take care to properly dispose of them. if you have had them in previous years, dig lightly around the soil and pick out the grubs in spring.
2) Row Covers
You would need to cover your rows while the beetles are in flight, most of June and the latter part of may.
Good cultivation practices will bring the larvae to the surface and you can hand pick and destroy.