If you check your roses now you might find these gregariously chomping away on the leaves. It is possibly one of 2 species of sawfly Arge pagana or Arge ochropus, and it is hard to tell which in the early instar stage. But if you can find the original egg scar on the stem you will know what species it is for sure. If it has a double row of cells it is Arge pagana, and a single row determines Arge ochropus. From my own past experience, unless you get a whole army of these chomping larvae they won’t seriously damage your rose. Sometimes the birds will grab them for protein.
Or maybe I should I titled this blog ‘Last One Munching’. I have been watching these Large Rose Sawfly (Arge pagana) larvae for the past few days, and how they have chobbled on my rose leaves and how they have grown fat on them. This is the final instar stage and the others had dropped off the leaf into the garden border to pupate, and this was the last remaining one, still merrily chomping away. This was yesterday afternoon. This afternoon it had gone, too. Below are some images I took a few days earlier.
I couldn’t believe that with all those rose-bush leaves they were all trying to nibble on what little was left of this one.
September 2017, rear garden, Staffordshire, England.
They have been at my roses all summer so far, and they are certainly making a meal of them. These are Large Rose Sawfly (Arge pagana) larva, young instars most likely. And four of them seem to like this one particular leaf for some reason. I feel sorry for the top two, for when they finally meet in the middle it will be the guy sitting on the branch he is sawing off scenario. Or maybe it won’t come to that.
Rear garden, Staffordshire, England. July 2017.
Please click on an image for a larger more detailed view. Clicking a second time may get you a little closer.