|The Japanese Beetle
I really shouldn't complain about them. I pretty much have a job because of pesky bugs and weeds. Although, seeing their skeletonized aftermath, there's nothing but frustration brewing under the collar. I can't help but wonder what our gardens would look like if the Japanese Beetle never made the journey over the ocean ages ago.
|Photo Source: Kentucky College of Agriculture
In late July and early August, the hotter the weather the more they congregate on the top of plants - near blossoms or tender leaves.They start at the top, working their way down the plant. A group of beetles attracts more beetles. Once, I counted at least 20 beetles on one unfurling rose.The beetles are most active during the hottest part of the day (noon-to-three).
|Eating Parthenocissus quinquefolia - Virginia Creeper
One of the reason's they are so rampant, is because of North America's love for turf. They overwinter as grubs in turf. When roses, fruit trees and other food interests are closest to turf, the more they get attacked by the beetles.
|Congregating on top of vine
|The beetles make dozens of holes, until most of the leaf is gone.
2) Japanese Beetle Traps: There are different kinds on the market. Some are pheromones mimicking females - attracting males and others attract the beetles with a food source. Both are quite effective. As when two or more beetles are gathered, more come round. Sometimes, unfortunately - the traps attract more Japanese Beetles to your garden from the neighbourhood than before. It's best to place the traps downwind at the furthest direction away from the path of highly edible plants that the beetles love. In my experience, walking slowly by your roses or infested plants with the Japanese Beetle trap, will encourage them to follow you. As I was hanging the last trap I placed, about 5 beetles gathered at the top of the trap before I even fully secured it. It works.
Another control is planting material that isn't attractive to the Japanese Beetle. Know the plants that Japanese Beetles devour: Here are 2 comprehensive lists
Be persistent and look for the typical hole markings they leave behind.
Best of luck!