Knowledgebase
Black Weevil Damage? #876918
Asked July 12, 2024, 7:31 AM EDT
Hamilton County Ohio
Expert Response
megachile bee. See the attached image: Friend or foe? Leafcutter bee or black vine weevil:
Source:
Okanagan Master Gardeners
https://www.facebook.com/groups/<personal data hidden>8334/posts/<personal data hidden>69060
Here's more information on leafcutter bees: https://marylandgrows.umd.edu/2022/05/09/bees-to-look-out-for-leaf-cutter-bees/
It is important to determine what is causing this current damage before "spraying with something." If it is the bee, pardon the expression, but the recommendation is to let it bee. You can remove the damaged leaves individually if it is too unsightly.
Also, imidicloprid is a powerful systemic pesticide that will remain effective in the soil/plant for a long time. Here is additional information on dealing with black vine weevil. https://www.missouribotanicalgarden.org/gardens-gardening/your-garden/help-for-the-home-gardener/advice-tips-resources/insects-pests-and-problems/insects/beetles/black-vine-weevil#:~:text=Nematodes%20can%20be%20applied%20as,Steinernema%20carpocapsae%20and%20Heterorhabditis%20heliothidis.
"Integrated Pest Management
We now use the term "integrated pest management" because we know from experience that there is no magic bullet to rid the garden of unwanted pests. We can merely attempt to keep pests at tolerable levels and minimize their damage—this is management. When using integrated pest management, remember these four important principles:
- The mere presence of a pest does not warrant control; determine a threshold for damage.
- Monitoring is essential, as is proper identification of the insect.
- Reliance on a single control technique will eventually fail. Use cultural, mechanical and biological control methods first; if those prove ineffective, choose the least toxic chemical control available.
- Go back to see if your methods were successful; if not, make appropriate adjustments.
Insects will always be present in a landscape; the key is to understand which insects are a threat, and which are merely pollinating or preying on other insects.
Complete reliance on pesticides, whether organic or not, can be harmful to beneficial insects and can actually make a problem worse by killing off the natural enemies. In order to manage pests and their damage, integrate your approach and use cultural (and mechanical) control (i.e., resistant plants, traps, crushing and sanitation) and biological control (i.e., predators, parasites and diseases) in conjunction with chemical control."
From: https://ohioline.osu.edu/factsheet/ENT-65
Whenever using chemical controls, always follow the instructions on the label.