What kind of beetle are these? And how should I get rid of them?
CLOSED: Beetle eating my coreopsis
These are coreopsis beetles (Calligrapha californica); they feed almost exclusively on coreopsis.
Controlling these beetles can be difficult. They damage plants so quickly that it’s often too late to reach for a chemical control. If you notice their caterpillar–like larvae in the spring when they begin feeding on coreopsis, direct hits with a commercial insecticidal soap may get rid of them. If that doesn’t work, try using Bacillus thuringiensis var. tenebrionis (Btt), an organic microbiological insecticide that may kill the larvae. Mix 4 tablespoons of a Btt product in 1 gallon of water and spray all plant surfaces thoroughly, including the undersides of leaves. Follow the label directions for specific mixing instructions and reapplication guidelines as product labels may vary. Adult beetles are most effectively controlled by handpicking and dropping them into soapy water to kill them.
Thank you! I have been picking them off - probably 400-500 so far on three small plants!
Post a Reply to this Thread
More Insect and Spider Identification Threads
-
SOLVED: Beetle eating my coreopsis
started by Jabeka
last post by JabekaJul 04, 20232Jul 04, 2023 -
SOLVED: Beetle eating my coreopsis
started by Jrockca
last post by JrockcaJul 04, 20231Jul 04, 2023 -
SOLVED: Beetle eating my coreopsis
started by Jrockca
last post by JrockcaJul 04, 20231Jul 04, 2023 -
SOLVED: Beetle eating my coreopsis
started by PitterCol
last post by PitterColJul 05, 20232Jul 05, 2023 -
SOLVED: Beetle eating my coreopsis
started by JStPaul
last post by JStPaulJul 08, 20231Jul 08, 2023