FWIW. I know people that raise caterpillars and I know from their experience that if the plant had ever been exposed to a systemic insecticide it usually kills the cats, even months later. What it will do to bees down the road I couldn't say and won't even speculate.

If you are at all concerned maybe you could try something like Safer's or a pyrethrum based spray. It may take more work but there won't be any lingering after affects.

I am not against pesticides either.

SCG

I would try it on a few plants and see if it works. Best to isolate those plants if you can so more mites can't just wander in. My guess is that it won't work though. Whenever I find mites on plants I immediately throw them out... not very helpful when you have a greenhouse full, I realize.

Have been doing more research on this and my personal opinion, after reading many articles, is that the neonicotinoids (poison in the systemic pesticide) would have little if any impact on the bees in my yard. Here's why: the plants I'm using it on would be mainly used on my patio and in some flower beds. My pesticide-free yard however, is about 2 acres of wildflowers, flowering shrubs and trees. The few bees that will visit my patio instead of the rest of the yard would probably garnish very little pollen from my begonias and calibrochias by comparison.

SCG - it makes sense that the caterpillars die because they actually feed on the plant that has been treated. This tells me it stays in the plant tissue for quite awhile after treatment...which is good. It's hard to find a definitive answer as to whether the poison is in enough concentration in pollen to kill a bee. Certainly a few plants would not, although using it in entire fields may be harmful to a hive that collects alot of the pollen.

don - (smile) No, no isolating going on here:

have you thought about making your own nicotine spray first?
have you tried the buttermilk and flour spray on them,
this will suffocate large swaths of them with every treatment?

neonic's will become part of the bio-dynamic atmosphere

either way, i hope you can get the little beasts under submission

I use a product called SM 90, available from hydroponic stores. I needed something that was environmentally friendly and would kill pests and that's what they sold me. I've used it several times and it works. Just make sure you spray about 7 days apart to get everything.
http://www.ebay.com/itm/Nutrilife-SM-90-SM90-multi-purpose-wetting-agent-pests-/390210106329?_trksid=p2054897.l4275

Neem oil, as a spray and soil treatment, will act as a systemic, with out putting yourself or the environment in jeopardy. It will not cause overnight destruction to pests, but rather acts as an antifeedant/deterant. Best used as a preventative, or in rotation with population knockdown measures.

Cold pressed is prime, as some heavily processed oils have the active ingredient Azadirachtin removed, and can be obtained at health food stores/natural pharmacies.

Spray water temperature and a good surfactant are important, to ensure proper emulsification and even spread. Warm water (70-80*F ideally) is important, as cold water will coagulate the oil, and hot water will reduce its impact.

For a soil drench to combat fungus gnats, root aphids, etc, 5-12ml per litre, mixed with an equal part surfactant (liquid soap, potassium based. Dr.Bonners preferably.)

For a spray, I use a 1% concentration with an equal part surfactant

Companion planting, trap crops, etc. There are many ways to control pests, a multi pronged approach is best.

SM90, with its nose tickling lemony bleach odour, is halfway between neem and Avid. Mainy comprised of canola and coriander oil. It does not work as a systemic, but is good to knock populations down, while rotating with insecticidal soaps and other control measures.

Dr.Bonners works wonders on its own, at 1% concentration. Peppermint brings the added benefit of peppermint oil, an insecticide in its own right, and Lavender will act as a deterant.

Ensure complete coverage of the plant, with particular focus on the underside of foliage. Spider mite eggs hatch every 3-5 days, an it is advisable to spray every 3-4 days until a measure of control is achieved.

As with bringing anything new into the garden, test a small plot or single plant at different concentrations, starting low, and observe results over 3-4 days.

I have been searching for the answer for ridding my kumquat tree of spider mites. I finally put it in the shower and that did the trick (4 awhile). Now they're back. Most of what I've read is what Miguelovic has said. Neem oil doesn't kill them but turns them into tweakers so they don't eat anymore and they lose their desire to procreate. Soap insecticides help diminish populations. And for the best results, rotate the usage of all of these. I understand that spider mites HATE humidity and will only populate drier regions. In my case, I thought about getting a humidifier (since I live in a dry climate n winter is coming 2, which dries the air out even more). I may try the shower one more time before I begin a regimen of death to the mites, but I am determined to get rid of them.

I have tried a solution of 70% isopropyl alcohol diluted in water and a drop of dish soap. I sprayed every day for a week, so far, so good. I have even used the 70% alcohol full strength on my citrus without any adverse affects. When I used it full strength I sprayed only one small branch of leaves and watched it, 4 weeks later and no difference in leaf quality, and no bugs either.