Just thought I'd add, all my trees are dwarfs in pots. It will all be very small scale work.

Jude, I apply imidacloprid in early to mid-June (Bayer Advanced), then again, in December. I use two applications to cover both CLM and any possible psyllids that will eventually be in my area (just a matter of time). We usually see CLM damage starting in July here in SD county. This gives the product enough time to be absorbed by the roots and taken to the leaves.

Patty S.

Oh my gosh you are fast Patty! I was hoping you would see this since we are fairly close.

Thank you for the info. I will go get some of that.

I posted on the fruit forum about Pluots. Are you growing any of those with success?

See this
http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn74137.html

Also, contact your county's Extension Service office for more specific info
Use this map
http://www.csrees.usda.gov/Extension/

Here is a link that might be useful: locate your county's Extension Service office

Hi Jude, I applied Bayer Adv. product (with imidacloprid) in mid June. I didn't see any evidence of CLM until a couple of weeks ago. Some new shoots have CLM damage, others none at all. Some damaged leaves look like the small CLMs began to mine but just stopped after a few switchbacks ( i wonder if they got sick and left the leaf!?).
The bottom line is that they still caused damage this year. I have not treated with any oils or other product due to the relatively high daytime temperatures (mid 80's to ~ 90F).
I would be curious what others in California are doing!
George K.

George, I think it's been a particularly a heavy pressure season for us in California with CLM. I have had a little damage as well. Same as you describe. They did indeed get "sick", but if you look closely, you'll see the larvae have actually died in the leaf. I decided to spray just the newest flush with Spinosad and I may end up applying my second dose of Imidacloprid earlier. It's been a tough year for CLM.

Jude, yes, growing several different pluots with success :-) I'll go over there and give you my varieties.

Patty S.

Patty,

You might want to re think the timing of your imidacloprid. I use it on my Meyers because it kills anything that eats or sucks on the leaf; and because it doesn't kill the beneficials. The recommendation is application every 6 months; but I find that near the end of that 6 months the effectiveness becomes less. Same with the Bayer fungicide that I use. Because of that and the fact that I am in an area that is infamous for bugs and fungus, I am now applying these chemicals 3 times per year.
I'm not recommending that you or anyone there use 3 applications per year; but you might want to re-time your applications so that the weakening of the systemic does not occur at the peak of the CLM.

Well, normally I don't see such heavy CLM this late, John, so the timing has worked okay up until now, but, we're getting all the pests that were in the abandoned orchard now moving over to us, as all the trees in the orchard are just about completely dead, now. We've had a flood of roof rats, snakes (following the rats), and all the insect pests. Sigh. So, yes, I may have to move to a second application of Imidacloprid at the end of July/early August, now. Just too many trees to try to spray with Volck & Spinosad, but for me, it does still work (and too warm usually in August to use it with Volck). I think that in Florida, they're using 4 applications to try to keep the psyllid infestation controlled, so I may have to bump up to 3 applications a year, and spread them out to every 4 months. Hate to use that much insecticide, but, we have the psyllid in N. San Diego county, found about 10 miles east of me, so really, it's just a matter of time until the psyllid is discovered here in my area.

Patty S.

Immensly helpful info - thank you!
Patty: yes i have confirmed the tiny critters are dead in their track.
Since these are caterpillars, i am curious if anyone may have tried or had success with "caterpillar killer" sprayed onto the leaves of Citrus? [Its a bacteria that is intended for use on various vegetables/flowers]. I use it for petunias and it works very well - it gives the caterpillars indigestion and they die.
Now if i only could get the deer away from those Petunias!

Patty - here in the foothills of Mt. Diablo we have those climbing roof rat battles too. I think I've made my yard cat, hawk, and Owl friendly.... I have eliminated any dense vines or vegetation along the ground - the rats have nowhere to hide. It seems to have gotten the population way down. The King snakes seem to be growing larger too.
good luck!
George K.

George, I am guessing you are referring to BT, or Bacillus Theriogensis treatment. I have used it very sucessfully on my pecan trees to control webworms (tent caterpillars). The caterpillars ingest the bacillus bacteria which causes them to get sick and quit eating. I would be very interested if someone knows otherwise but I'm guessing BT won't work for leaf miners since the BT is applied to the surface of the leaves and the leaf miner stays inside the leaf. The nice thing about BT is that it's relatively non-toxic to us humans and to other beneficials such as bees.

yes, JohnOrange, i am pretty sure that is the stuff!
[[the BT is applied to the surface of the leaves and the leaf miner stays inside the leaf]]

Indeed, this is exactly what my concern about its effectiveness would be. However, just maybe they'd ingest enough in their initial tunnel(ing) into the leaf?

Perhaps a long shot, but i have some and will try it out on trees that i have not treated with Bayer Adv.

George K

This post was edited by Becauseican on Thu, Aug 29, 13 at 15:32

George, I'll be interested in what you find. Maybe some of the BT will enter the stomata of the leaf and the miner will ingest BT even while staying between the epidermal layers of the leaf. I have also had a bad year with leaf miners on some seedlings and particularly on one I have potted and wanted to look nice for an indoor tree during the winter. Perhaps folks with potted plants could leave a fan on them during morning and evening so the delicate moth would not be able to even approach the trees?

UC IPM does not suggest Bt for leafminers; and if it were effective, I am sure it would be one of the first suggestions. No harm in trying it that I can think of; even if it only reduces the infestation, it is a help.