Hate those things. None noticed here as yet.

I don’t see them yet either, but I know their coming! They make everything SO ugly! As for picking them off? Who has the time with so many roses? Lisa

I know, Lisa. With the delayed spring here I have a lot to do and squashing rose slugs wasn’t on my list, but perhaps I will get ahead of them this year. They are tiny.

Ignoring them can have some pretty ugly consequences. Here are a few photos of 'Lynnie' taken 06-19-2017

Lyn

Great awful photos Lyn.

Yep, those are “great awful” pictures for sure! I’ve really noticed that my roses that are in my hottest and driest positions suffer from rose slug damage the most. I’m not sure if it’s this heat stress making them weaker, or the fact that those beds are also filled with much looser (purchased) soil. Perhaps the rose slug larvae has a nicer life in this loose soil, than in my native heavy clay. Maybe it’s a combination of both factors, the nice loose soil and the broiling heat stressing those roses. I definitely see the worst skeletonized leaves on those roses. Either way, I hate them! I do have a zillion birds in my yard, more this year than ever. I’m hoping they will eat them up for me! Lisa

I have a bad time of it with the rose slugs. I have spent many hours at a time hunting, picking, and squishing, week after week. Last year, I finally began spraying with the Cornell mixture or something like it (horticultural oil, soap, baking soda solution) and it was very very effective! However -- it must be repeated regularly, and I got behind on it. This year -- I'm vowing to do better.

I hate those critters! Good luck.

Sheba

Sheba, did you need to carefully spray the back of the leaves for it to be effective? I am willing to spray if it isn’t as time consuming as seeking and squishing! Thanks.

Hi, Deborah,

You need, I think, to really cover the whole thing, and especially the undersides, as that's where they seem to hang out. It's certainly faster to spray than to hunt & squish, IMO! You need a good sprayer, though. I bought the Solo sprayer (in the larger size, which is still too small).

What's great about this sprayer is that it has a little swiveling cone at the sprayer tip so you can hold the sprayer beneath the leaves and it will direct the mist upward, coating the underside of the leaves easily. But it's not a perfect device. It does sometimes leak around the screw-on cap, which gets me wet (which would be dangerous for anyone using for chemical applications or bleach sprays for cleaning, etc). I have a very tiny garden and am spraying @25 small roses. For a bigger garden, you'd go nuts having to remix & refill the thing.

But -- yes, much much easier than hunting and squishing. And -- from my limited experience, the Cornell formula really seemed very effective for the rose slugs. You do need to reapply.

If anyone has a recommendation for a better sprayer, I'd sure love to hear it. Do those sprayers with the little hoses make it easy to spray from underneath the leaves? That's the critical thing, I feel.

I haven't seen any of those awful critters yet, but I'm sure they're coming soon. I'm gonna try to get my first round of spraying done this week. Good luck,

Sheba

Thank you for the detailed response. I may need to invest in a good sprayer and give it a try. I have around eighty roses, some of them quite large, so squishing is an endless task.

Yikes, I can't imagine trying to squish my way through that many roses! You deserve a medal. Hope the sprayer system will bring you some relief.

They have made their appearance here as well as the beetles. Last year, slugs but no beetles. I thought I had finally gotten rid of all of them. Wrong again. Sigh.....

I am trying a new experiment this year to reduce the population of rose slugs. Do I know if it will work ? Nope.

When I researched rose slugs, I learned that the saw flies lay their eggs on the edges of the foliage. I decided to wash the foliage with a strong stream of water with the hope of dislodging some of the eggs. Maybe I will reduce the population of rose slugs. So, I have been washing down my roses almost every day.

After the eggs hatch, I plan to pluck leaves instead of squishing slugs. Since the foliage is going to be destroyed anyway, the removal of the leaves is not going to cause worse damage than the slugs. The goal again is to reduce the sawfly population. If the slugs are not allowed to grow to maturity and then drop down into the soil to pupate over winter and come up and lay eggs next season, it's possible I've made a step towards reducing the population of the flies.

If you look at my photos in my earlier post on this thread, you can see why I can't just do nothing. I have about 100 roses on four different levels. At least I have a plan.

That's a good plan. I suppose even if you have to defoliate all your first leaves, more will grow and it will only mean a delayed flowering. If it were bad enough I might consider defoliating on purpose with lime-sulphur, although it does seem a bit extreme! Since I'm covering my soil with landscape fabric for midge, I'm hoping this will help with the sawfly, as well. While not AS bad as yours, roseangellyn, it's still pretty bad in my garden. Mine continue to lay eggs all season!

I was wondering if landscape fabric might help. Please let us know your results.

I will! I have to remember to cover my potted plants as well. That's a good job for an intermittently rainy afternoon.

The most 'benign' (this taken with a pinch of salt) insecticide that will control the sawfly is spinosad. Sawflies are about the only reason I still spray my roses once in a blue moon.