I think you used 3n1 rose product by Bayer. Pretty strong stuff. That's sawfly damage. Look under the leaves and you'll see small green worms that look liked, but aren't caterpillars. While the damage is generally cosmetic, it can deprive the rose of leaf surface area if it's really bad. You can squish them, brush them off or spray them off with strong water. Tobacco tea also kills them without the residual affect of a systemic neonictinoid.

My suspicion is a water deficiency but I did not want to point ppl to that decision. It gets some serious hose time every 3 or 4 days w/o rain. That poor subdivision layout drainage control mound it is on appears to be half super compacted subsoil and half mulch. Its quite interesting. At the beginning of the summer it had a day with droopy leaves which made me think it needs more water than most things I plant. So that leaf damage is typical of Cornus florida drought stress? I didn't even see it on my established ones in 2012 when we had a real hot summer and drought.

when my P sylvestrus started doing that .. in tree time.. is wasnt long before i had to remove them ... couple years or so ... and yes.. near the end.. the sapsuckers attacked ... that is what you might know as amber [given a couple million years ... lol] ... pine sap ... aka: resin ... it is incredibly fragrant ... and if you had a scentless candle.. and put a bit in some melted wax... it will fragrance the room ... https://duckduckgo.com/?q=pine+sap&t=ffcm&ia=web https://duckduckgo.com/?q=pine+sap&t=ffcm&iax=images&ia=images https://duckduckgo.com/?q=pine+sap+in+candles&t=ffcm&ia=web but.. all that said.. the tree is a goner.. imo .. sooner or later .... ken

There's always some damage, but it seems more widespread to me this year -- four-lined plant bugs on the caryopteris, something chewing the heck out of my cactus zinnias, who knows what munching on the squash and cukes, explosion of asparagus beetles, and yowza did every ant in the county take up residence on my property? I've never seen so many ants in trees and shrubs. I thought some of my milkweed bit the dust but when I looked closer I noticed green stems had poked through but was chewed off -- all of the stems. I dug them up and potted them, figuring if I get them away from whatever's going after them they'll survive just fine, and then other milkweed had something eating just the tips, probably some sort of borer, so I had to cut those back to below the damage. I think it's just going to be an ongoing battle this year...