Dave and Susie want to know, “What’s eating my roses?” Many culprits are possible: caterpillars, grasshoppers, squirrels, etc. Luckily we have a photo with eating marks that definitively indicate who is eating the leaves on Dave and Susie’s roses.
Here we see holes that are:
(1) always oval to circular is shape, and
(2) all eating holes are always on the leaf edge or leaf “margin.”
These two factors clearly identify the culprit as leaf cutting bees. When I tell people that bees have done this, I know that most people do not believe me. Leaf cutting bees are quite common on the entire west coast of North America, from Canada to Mexico, and they do their cutting in the summer time.
The bees mouth parts are situated such that, like a grasshopper, they must begin eating or cutting on the edge of the leaf. Then they spin in place while cutting, resulting in an oval-shaped or somewhat circular-shaped hole. The little piece of leaf is taken back to where the bees are nesting and used like a thatch.
To prove all this, I found a nice YouTube video.
Caution: some of the still photos later in the video are NOT from leaf cutting bees.
If you see holes in the middle of leaves, it’s not due to leaf cutting bees.
Damage from leaf cutting bees:
(1) Produces holes almost circular in shape.
(2) Is always located on the leaf edge/margin.
What to do about it? Do not do anything! Bees are good to have around!