And how to treat it.
This may be Plum Curculio. Here's a link with more information about them:
Hello, these link might be Helpful
Take an infected leaf to your local nursery. I find they are very helpful and can help you with the products to fix it. Good luck.
Here's an article that might help - https://www.almanac.com/plant/plums
Hi Parv: Perhaps this site will help: https://candidegardening.com/US/stories/9172ae8f-67ee-4e85-b902-577bfbf60969 Good luck
This is a close up of a plum curculio. The picture you attached does not look like this.
Those are bad pests and lots of eggs. At the very least, give the whole tree a gentle blast with a water sprayer. I would squish the adults and get rid of the eggs.
If the washing & squishing isn’t working and it is bearing fruit,
then spray it with Sevin every week, until 7 days before you want to harvest the plums.
These are CARPENTER ANTS, I lost a tree about 15 years old & they ate the roots & the tree fell almost hiting my husband, Kill everyone you can with seeds you can buy at LOWES hardware, They will get into your home & nest too.
They are not carpenter ants.
This is what a carpenter ant looks like.
It has 3 segments and the legs are not spaced the way the insects in question are where the abdomen is sticking out the back and pointed.
I was looking for a plant insect guide and came across this. Maybe your insect is in here and it will tell you what to do. https://www.gardentech.com/blog/pest-id-and-prevention/plant-pest-detective-identifying-common-plant-pests
Try knocking them off with a strong hose. THen get an ant trap to kill any more
Thank you so much everyone, I spray soapy water and is works alot,
Send the picture you sent here to you local agricultural center. Every area has one. They can properly identify the insect. The shape is much closer to a lady bug larvae but they are two toned, not all black.