I was trimming the dead wood from my Hydrangea by my deck and I kept noticing these orange yellow things flying around…thought they might be lady beetles(didn’t have glasses on)…not red enough for a lady bug. Then as I got closer to my Knockout roses I saw that all the leaves were eaten off the plant. Thought maybe a Japanese beetle at work. I didn’t see any in that area. Today I noticed one of my new roses I planted had 3 blooms on it. I wanted a closer look at them. I noticed at the top leaves were eaten away, similar to those of the Knockout rose. Then a few stems down…here is what I found:
leaf-feeding larvae
Sawfly adult feeding on pollen
I picked that cluster of leaves off and fed the larvae to my pond fish. With a quick inspection, I see no additional in that immediate area. Although, I’m sure I need to watch vigilantly. I walked over to another new rose and saw this:
Well sawflies are the culprit. So now to take care of them. I just recently saw an article to be on the look out. Eggs will hatch in 2-8 weeks after the fly deposits them (They deposit them in the soil in spring). Of course seeing the larvae, I can assume they’ve hatched. However, it might be a continual process. Most likely the white spots on the leaves and holes in the photo are damage due to larvae.
So in reading, I find that insecticidal soap or spinosad, an organic substance made by a soil bacterium. It can be toxic to insects . Some insects have become immune to spinosad and it should be used as a last resort. I just happen to have purchased some at the beginning of the season. I will use it as a backup after first trying to spray and pick them away. I wanted to share this just in case someone else is seeing these signs. I hope not. I will keep you posted on my progress.
Monroe County Master Gardener Association 
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