Strange black spots on cuke leaves
Hello ~ and thank you so much for any advice or opinions in advance! I'm really excited to be posting here (this is the first time I've had a garden do this well!)!
My question involves strange black spots/schmutz on my cuke leaves (I'm also finding the same or similar spots on my neighboring grape leaves, too). An internet search led me to believe that the black spots were the result of gypsy moths/caterpillars, so I found BT spray at my local Lowes, which I then sprayed all over my plants.
Ideally, I'd like to make sure that I'm treating the problem correctly and haven't confused these black spots with other black spots. I've uploaded/attached two images that show the spots.
Any help is VERY appreciated! Thank you so much!