Alan, if you're going to use oil, it's best done early in the morning or later in the evening.
You say, orchard, so I'm assuming you mean numerous trees..is this correct? If it were one or two trees, and scales were few, plucking would be the best way..But if you've many trees then something stronger like Neem would be best. I've also heard Fish Emusion helps, by using as a foliar spray, but haven't tried it, (yet) so can't say for sure..I hope you rid those bugs, they're real pains..Toni

Alan I use horticultural oil in the summer, it is lighter than the dormant oils & doesn't effect the active growth of the trees. I mix mine with a insecticide spray as well. Don't use dormant oil in the summer as from my experience it is very heavy and does damage the new growth leaves.

Hi Alan:
I'd suggest trying that "summer oil" on a small "test area" on one tree. Like Laaz, I've had excellent results in controlling problem insects (mine) in a hot summertime greenhouse. Toni suggests applying during the cool periods of the day, I agree, I usually apply in the evenings. Although I've never tried that product on "trees in the ground" I'd expect that it will do the job. Good luck! Joe n CO.

I can mix the oil to the summer recommendations (Ortho's Volck oil) but I was concerned about using it at all with it being so hot and all this time of year. So if I mix it light as per the directions and apply it in the evenings does anyone think this would harm the trees?

Lately it's been raining more in the early afternoons than evenings so I should be able to get it sprayed and dried on the trees before it rains again.

.....Alan.

Alan, please be careful! I caused major defoliation of my citrus by spraying with a light oil mix during hot weather. I did spray during the coolest part of the day (ha) but the results were awful to see. Check the directions. After I messed up my trees I went back and read the entire direction folder. it clearly stated not to use it in summer. My fault entirely.

Lisa

Be sure it is a citrus-rated oil; Volck should be fine, or a Florida FC-435-66 or FC-412-66. As has been suggested, spray early morning or late evening. July is the single most popular month to spray commercial Florida citrus, with several hundred thousand acres sprayed each year. August is probably second most important. So it can be done with good results. Many commercial sprayers work at night. You'd like to have the spray droplets dry with the temperature below 80 degrees, if possible. Last evening, here, it dropped to 74 just after a storm, and didn't rise to 80 until around 9:00 a.m. today. So there would have been a good opportunity.

I also agree. BE CAREFULL. I spoke to my nursury about problems and they gave some fish emulsion spray. I sprayed my 4 citrus tress (I think a little too much) during the middle of the day. I had some little leaf drop on 3 trees and major leaf & Fruit drop on the 4th. It's finally showing some new leaf sprouts. I'd put it on at dusk and not too heavy. Oh but it did work great and natural.

Knepper, I am really glad that you brought up the problems of using fish emulsion as a "insecticide" against scale, mealy bugs, aphids and ect. Fish emulsion is probably the LEAST refined oil of them all, and is, of course, a heavy oil. It is in the crudest form of any of the oils. I can see where using it in place of a highly refined horticultural oil would cause many a problem. Besides it smells badly, and is not labled or recommended for that use. - Millet

Knepper, I was told by the owner of Harris Nursery, they've been using FE as an insecticide over 40 yrs. It's safer than other products...the thing is, it's IMPORTANT to follow container directions..If you apply too much of any insecticide/fertilizer it wil harm a tree..This is the reason I use half the recommended dossage when I fertilize plants of all types. Some ppl think a little more food will boost plant's growth, when in fact, it can not only defoliate, but kill a plant.
She, the owner of Harris said, 2 teas per gallon of water, is adequate..Actually I'm going to foliar spray my citrus w/FE come fall before they come in for winter..I will use 1 teap per gallon..FE is good because not only does it keep bugs at bay, but feeds plant too..And since I refrain from fertilizing in winter, (I'm in IL) this will be their final feeding until new growth resumes.
I've seen too many posts where ppl used Neem/oils and had defoliation problems soon after..Toni

Toni, in actuality Harris Citrus could get into very serious trouble with the EPA, if EPA ever found out that they are making recomendations to their customers, verbal or otherwise, to use a product that is labled as a fertilizer as an "insecticide" to kill insects. I know this from experience, as our company was fined $50,000.00 in 2001 for making use claims on a product that were not on the product's label. The fine was eventually reduced to $17,000.00 and our company was given one year to pay the fine. One of our competitors notified the EPA,and they came and whent through our files. A company cannot make any recomendations that are not expressly written on the label, and ABSOLUTELY CANNOT tell customers to use a labled fertilizer product as an insecticide to kill insects. All it would take is for just ONE PERSON to make a telephone call to the EPA and Harris would be in huge trouble. It is also illegal to use a insecticide at higher OR LOWER rates than is written on the label. A product label is considered as a legal document. - Millet

Millet, I just spoke to my husband who is one of the top managers at the IEPA..Illinois Environmental Protection Agency. He said, there's a lot of red tape involved in what you say..Because a statement was made as opinion, not by the manufacturer trying to get away with something other than the products actual use, this would be avoided..The EPA has more important issues then an employee making a comment/opinion to a customer. It just doesn't hold up. And why would this comment be written in records where the EPA or any government agency bother to read something someone 'said?' Toni

OOOOHHH NNNNOOOOO.... Before this starts could there be a quick look at the posting ""looking for trace mineral supplment solution""YES or NO is fine...Dale

Toni, your propably correct that the EPA would not bother with one or two recomendations. But if they keep it up they could very easily wind up with a fine as our company did. The EPA's earn a lot of their keep by doleing out fines. The sad part of the whole EPA thing is that it was started by a Repuublican preaident... R. Regan. EPA a good thing GONE WAY TO FAR. - Millet

Here in the UK, now that the House Sparrow population has declined, we have a flock of Long Tailed Tits, 14 at the last count, that graze the Meyers lemon and the Citrus Limon trees and seem to be keeping the scales under control. A few various Finches join in as well, but its the LTTs that seem to be doing the bizz.
Nik