Paper Wasps love them and will patrol the Roses daily and gobble them up before they do any real damage, for future reference.

Are there too many Rose plants to hand pick them? That's the only surefire organic method I've heard, yet.

Barb - I don't think we get paper wasps around here, or not enough of them anyways. Sawflies are a real problem where we live, and we get many different types. No, there aren't too many rose bushes for her NOT to hand pick, but would she be willing to take the time to do regularily is another question! I noticed that her rugosa is not as vulnerable, or maybe she got lucky, and the sawflies missed it altogether. They are agressive, and not very discriminating when it comes to depositing their eggs. So, it's hard to choose a variety that's perhaps less appealing to them. The only rose I haven't had a problem with this year is my climbing Eden; all the rest fall prey! I've many roses in MY yard, and although I prefer to refrain from using chemicals, I haven't a choice but to keep the sawflies in check with a contact spray once a month, and it works! I'm not sure about my neighbour, though, as she's strictly an organic gardener.

I've used BTK (Bacillus thuringiensis - Kurstaki) when squishing them by hand was too time consuming.

They are generally uninterested in rugosa and rugosa hybrids in my experience. I hand pick and use insecticidal soap. You have to inspect your roses often to keep them under control.

Kimm - How do you apply BTK, and where can one get it?

Home Depot. It comes in a concentrate that you dilute. It needs to be fresh every year. Some nurseries hold on to old batches so you really have to check the date.

The clue is to check your roses frequently. If you get them when they're tiny, insecticidal soap will work. If you wait too long you've got a real problem. For organic growers shaking them off (if they are large)or hand picking is very time consuming but the only remedy I know. BT surely does not work. These critters are not caterpillars.

I agree with Randy and Veilchen. BtK will not work on sawfly larvae. It's a common misconception. BtK is specific to true caterpillars. One of the most common "failures" of BtK about which we receive calls are from people who misidentify sawfly larvae (wasp larvae) as true caterpillars. Sawflies have a different gut chemistry. Horticultural oil and insecticidal soap can do a number on sawfly larvae if they are applied when the larvae are small. Good coverage is the key.

Regards,
Colin

What do sawfly larva look like. Do they look like really little green caterpillars, or is that another pest?

Here's a picture.

Here is a link that might be useful: Sawfly Larvae

There are a couple of things that you can use to distinguish most sawfly larvae from caterpillars (with the exception of the slug sawflies and some of the stem borers). Look on the underside. There are three jointed legs on the segments following the head (on the thorax). After these, on the abdomen you'll see fleshy things that look like legs (called prolegs) and serve the same function. If there are 6 or more pairs or these things (including the one at the back end) then it's a sawfly larva. Sawfly larvae also do not have velcro-like grippers at the ends of these pro-legs. Caterpillars do but they're not always easy to spot, even with a good hand lens. A good link that shows a side view of a CATERPILLAR (identifying true legs, prolegs, etc.) is below.

Hope this helps.
Regards,
Colin

Here is a link that might be useful: Caterpillars

well if nothing else those links helped me a bit. Thanks

If you have enough small birds in your organic garden, you shouldn't have a problem with sawfly larve. Try putting up a hummingbird or wren feeder.

Otherwise, spray the underside of the roses weekly with neem oil.

One year I had a problem with sawfly larvae. I used beneficial nematodes per advice from this forum and it worked. It actually took care not only of the slugs but also thrips. I haven't seen them since. Of course, I had to re-apply them the next year to increase the population but it was great. I got the nematodes from Garden's Alive.

Do sawfly larvae curl up inside a rolled up, stuck together leaf or is this something else?

Does anyone have certain roses that don't seem to be affected by these devils? Last year my Climbing Pinkie was defoliated by them, Alister Stella Gray not as bad but pretty serious damage, while Belinda's Dream was pretty much untouched.

The rolled up, stuck-together-leaf guy is a leaf tier caterpillar. There are several species. Just squish them.

I don't know what controls the rose slug sawfly in my garden, but something does. I do have paper wasps.