Green June beetle

The genus Cotinis belongs to the order Coleoptera and the family Scarabaeidae. The most prominent species, Cotinis nitida, is commonly known as the Green June beetle. These insects are easily recognized by their vibrant metallic green coloration and their loud, buzzing flight, often observed during warm summer days.

These beetles are major pests for various horticultural crops, including stone fruits, grapes, berries, and occasionally sweet corn. The adults are highly attracted to ripening fruit, where they congregate in large numbers. By chewing through the skin and soft tissue, they leave behind significant damage that renders the fruit commercially unviable and prone to spoilage.

The life cycle begins with eggs laid in soil rich in organic matter or compost. The larvae, which are large, C-shaped grubs, spend their time underground consuming decaying vegetation and roots. They typically remain in the soil for one year before pupating and emerging as adults, which then move to foliage and fruit to complete their reproductive cycle.

Damage caused by Cotinis is primarily associated with the feeding habits of adult beetles. Because they feed gregariously, they can destroy entire fruit clusters within a short period. Furthermore, the wounds created by their feeding serve as entry points for secondary infections like brown rot, which can quickly spread throughout a harvest.

Effective management and control strategies include several integrated techniques:

• Maintaining good sanitation by removing and disposing of fallen, damaged fruit to reduce attractants.
• Hand-picking beetles in the early morning when they are sluggish and less likely to fly.
• Applying parasitic nematodes (such as Heterorhabditis bacteriophora) to lawns and soil to target the larval stage.
• Utilizing traps baited with fermenting fruit juices to lure and drown adults during peak flight periods.