Help! Nearly all the leaves on my mock orange bush have been consumed by this little bugger! Can you please help identify and recommend an arsenal?

It looks like a sawfly larva. There are some pics on the web of a "mockorange sawfly" that match but I didn't see any scientific name to properly ID it. One page recommended hand-picking them. I would think a direct hit with insecticidal soap should work. If nobody comes up with an exact ID by then I'll take a look in my bug books tomorrow.

Thank you! Recommendation where I can get insecticidal soap?

Most any nursery, or the garden center at HD or Lowe's will have it. I prefer the local nursery, and if you take a sample of the critter in with you, someone knowledgeable will advise you, as well. (put the crawlie in a jar or ziploc bag, though!)

For the insecticidal soap to be effective, you need to spray it directly on the little guys. Why not first try to pick off all the offenders and drop each one into a bucket with a bit of soapy water? Good job for the medium size to large children in the neighborhood.

I figured from your picture that yours was a sawfly because it looks like it has too many pro-legs to be a caterpillar, and a consequent web search brought up this page - the picture looks a likely match. Couldn't post it last night as I was on my iPad and for some reason I can't paste URLs into ATP from it.

http://www.walterreeves.com/ga...

another article, but with no picture, is here:
http://blog.syracuse.com/cny/2...

What I don't like is that no scientific name is given in the articles, which makes me wonder exactly what sawfly it is. If you do take it to a garden centre with you, make sure they count the pro-legs to differentiate, and don't try to sell you something that works only on caterpillars. Insecticidal soap should work for either. BTW I wouldn't take it in a plastic baggie, go with a jar. I found out the hard way that critters that can chew leaves can also chew plastic baggies and escape

Thanks very much! So, there's no preventative I can put on my plant to keep the little critters from coming back?

Some sawflies only have one generation a year so once they're gone they won't be back that same year. So it depends if this particular one has more than one generation, that's where a more precise ID would be useful. The links I gave above suggest it only has one generation, though, in which case once gone for this year it won't be back. You could just keep an eye on the plant to make sure. There are several insecticides labeled for sawflies, you could ask at your local supplier what they recommend and have available for them in your area. Diatomaceous earth can also be used for sawflies but whether that's practical or not would depend on the size of the plant and whether you mind its looking dusty temporarily.

Whatever you choose to put on your plants you should always be sure that it will be safe for bees. Thank you.

Thanks very much!