Cheyenne Botanic Gardens News and Events


Notches on the leaf edge?

If shrubs are developing small roundish notches on the edges of the leaves, less than a 14 inch, it is likely caused by the black vine weevil. The young weevils feed on the roots and then develop into adult weevils that then feed on the leaves. They feed mostly at night. Adult weevils can be somewhat controlled by capturing them cover Notches on the leaf edge?under boards adjacent to the plant and discarded daily. According to Colorado State University, adult feeding, as evidenced by leaf notching, can be controlled with sprays of certain pyrethroid insecticides such as bifenthrin, cyfluthrin, and lambda-​​cyhalothrin. These should be applied to the foliage and it can also be useful to treat areas at the base of plants, where they rest during the day. Control may be improved if applications are made late in the day or in evening, as the weevils become active and move onto the plants after dusk.

It is unheard of for plants to die from this pest so many people simple leave it be and put up with the more ragged leaf edges.