Sulfur does NOT act as a systemic pesticede whatsoever. Not only that, but such a soil application will adversely affect the soil pH and the soil flora and fauna. And.....not only that, wettable sulfur is so effective at killing beneficials that the pests get an opportunity to multiply, notably the spider mites. Yikes.

Wettable sulfur is a contact killer.

By far, the best control we have of spider mites are the beneficial predatory mites, and those are quickly wiped out by topical sulfur applications. That's why sulfur is associated with severe spider mite problems.

rhizo - thanks!

I must find some non-spray method. I switched from a situation of no neighbours in that part of the garden to a situation of neighbours with small kids. It's a small urban garden. I don't want to damage the kids' health in any way.

I understand that abamectin is systemic. Would abamectin soil drench or basal trunk application work?

I keep running searches on google. I just found this:

"The systemic insecticides imidacloprid
and abamectin are available and labeled for soil
drenching and/or soil or trunk injection"

The source seems to be reliable: Arboriculture and Urban Forestry' (it's in the link i've attached)

BUT, i also found an infor sheet from British Columbia government, which seems to state the opposite concerning soil drench::

"Environmental Considerations: ....
Plants do not absorb abamectin from the soil."

Here's is a link to the info sheet:
http://joa.isa-arbor.com/request.asp?JournalID=1&ArticleID=2833&Type=2

So now I'm confused, but application via the trunk still seems possible. I don't know how to do injections.

How does one go about smearing the tree trunk with abamectin? Which dosage would you use?

Here is a link that might be useful: Arboriculture and Urgan Forestry

Plants do NOT absorb abamectin from the soil. It must be applied directly to young foliage. You have access to complete on-line labels to every product, which should enable you to make a wise and responsible choice. Any way off label use is dangerous and illegal.

Imidacloprid is another chemical famous for causing an explosion of spider mites....in case you were going to ask.

I suggest that you look into the use of relatively benign horticultural oils. When sprayed to the underside of the foliage, oils smother adults and eggs of spider mites.

What kind of tree are you trying to protect?

rhizo as you can see from my additional post (just before your present post) I've already discovered that abamectin is no good as a soil drench.

I can't spray. I need to apply through the tree trunk, and according to the article from Arboriculture and Urban Forestry, trunk injections ARE POSSIBLE.

The trees I'm trying to protect are 6 crepe myrtles.

Would smearing the abamectin on the tree trunks (instead of injecting the trunk) work in your view?

WinterCat, I used to be quite skeptical of tree injection - until I saw the spectacular results against the spiral whitefly here in south Florida last year. Here is one (of many?) possibilities.
I have seen homeowners use injection kits quite successfully.
My opinion is that the method uses the least amount of chemical; the product is confined in the plant system and it targets sap sucking insects (Imidacloprid) or mites (Abamectin).
The University of Florida (the authority in my area) does not approve of tree injections because the method breaches the protective bark and can provide access for other and potentially harmful organisms.

Perhaps this article from the University of California about an Integrated Pest Management method of control for Spider Mites might be of some help. "In gardens and on small fruit trees, regular, forceful spraying of plants with water often will reduce spider mite numbers adequately. Be sure to get good coverage, especially on the undersides of leaves. If more control is required, use an insecticidal soap or oil in your spray, but test the product on one or two plants to be sure it isnâÂÂt damaging to them."

Here is a link that might be useful: Spider Mite Control

ronalawn - my three cats - harmful organisms in their own right - keep breaching the protective bark of my crepe myrtles, so I might as well smear abamectin right into their claw marks.

kimmsr - at the beginning of last summer I hosed the trees with strong upward jets of water every day for a whole week. it didn't work. I repeated the operation for a couple weeks more - no good. At that point I turned to chemicals, which do work.

Many thanks to both of you! I'll go for a trunk treatment with abamectin.

I strongly suggest that you contact the toll free number on the packaging to obtain the best possible advice. They can help you with off label applications.

Trunk injections are a specialization, requiring unique equipment in order to do the job with as little damage as possible. Even at that, it is only recommended for extreme situations.

rhizo - I'm not going to do a trunk injection. I'm going to smear the trunk with abamectin. From what I found on the internet, painting the trunk with systemic miticides works as you can see in the link attached.

Here is a link that might be useful: Getting Chemicals Into Trees Without Spraying

It's never been my understanding that abamectin works as a systemic. There aren't any systemic miticides, as far as I know.

Miticides containing abamectin are not systemic, but TRANSLAMINAR. When applied properly to foliage, it penetrates the tissue locally and is stored there for a period of time. It does not translocate systemically, not from the roots and not from the bark.

A safe and simple horticultural oil, when applied to bare branches in the dormant season, can be very effective in smothering mites and eggs. When applied to the underside of leaves, oils work very well towards smothering the adult population, too.

Oils are inexpensive, very safe around people and pets, benign to nontarget organisms, easy to mix and apply....all that and effective, too.

Here is a link that might be useful: click here for more information

rhizo - thanks for the link.

Re systemic miticides pls read atricle in the link I'm attaching. It's research on (among other things) Abamectin trunk injection.

The article mentions application by capsule and also by modified veterinary syringe under the bark. I rather like that. Don't you? Wnen I sprayed with oil recently I got some drift right in my face. Lucky it was just oil.

Here is a link that might be useful: Evaluation of New Systemic Insecticides for Elm Insect