Leafcutter bees seem like a good possibility, but have you done a nighttime flashlight inspection? I ask because I've been noticing significant damage on new growth, as well, and the culprit turned out to be Asiatic Garden Beetles. They're similar to Japanese beetles, but they're only active at night. Had I not been in the habit of making the occasional nighttime sweep to see what might be out and about, I never would have known that I had them.

I see them any daylight hour I'm outside. Most are green so they blend in well, but some are also shades of tan or gray. Grab your clippers, find one, then carefully, slowly sneak up on the danged thing with the clippers and cut it in half. Sounds gross but it works. Sometimes, you can actually grab them securely with the clippers. Then, you get the pleasure of slipping it under your foot to step on it. Works every time with no damage to the environment or beneficials. Costs no money, either. Kim

I use plain ole Sevin dust on the leaf rollers which attack my canna lilies. Applied early as they begin growing, it seems to insure they grow all season long without further leaf roller problems. This year, I was preoccupied with hosta anf forgot the lovely Phasion and Tropicana cannas, until now they are basically a mess. However, new leaves are emerging without blemish. A dusting of Sevin did the trick there. But it can also leave permanent signs on the hosta leaves, if you sprinkle it on them. I tried that on a couple of hosta when the sawfly larvae were messing with them, and quickly stopped. Now I use the Bayer spray with Magic in it to control those tiny worms, and reapply it whenever I see a fly hovering around a plant.

I try not to interfere with the complex interactions of flora and fauna in my woodlands.Favoring one species over an other is not my goal.Unless there is a clear indication of an imbalance cause by human disturbances,such as an import,or unless I,m protecting something that I was planning to eat,I usually leave things alone.Finding a new insect is sort of like discovering a new wildflower,it's part of the enjoyment.My gardening goals are to promote biological diversity on my proprety,to encourge the self-emmergent complexity of the ecological balance,and to restore my yard to the symmetry of primeval nature.Anything less is crayons.