Annie, I wouldn't use Mineral Oil on my trees..Either go w/an oil insecticide or Fish Emulsion. I've been using Fish Emulsion and it works fine. I didn't find any pests last winter on trees/plants that were sprayed.
HOw infested is your citrus? If mildly, you can pluck w/finger and thumb, then swipe w/rubing alcohol..even if you feel you got the little buggers, I'd still spray w/the fish emulsion or oil as a preventative.
BTW, I'd isolate the trees that are infested..scale is contageous and they'll find homes on neighboring plants. Good luck..Toni

Hmmm. Haven't heard of using fish emulsion as an insecticide. It's a fertilizer.

The suggested "pest oil" would be a highly refined horticultural oil, one that's suitable for plants with leaves.

Jean I hadn't heard of using FE as an insecticide until Toni suggested it either but it seems to be working. I haven't had any major infestations and don't know how well it would work for that but it's definitely kept my plants free of creepy crawlies. I won't use any insecticides in my garden so this has been a great solution for me. I've been using it monthly.
Karyn

I had a lot of scale bugs on my plants and all i did was just spray water at them really hard but not hard enough to rip up the leaves.

John

Scale are difficult to rid..even when u think u got them all, they seem to reappear. I have one olive tree that arrived w/scale when I got it. That was the only tree I didn't spray w/FE which was a mistake. Sure enough, even after hosing w/water and plant sitting in rain, it once again has scale..I'm going to spray that plant thoroughly. I hate those bugs..Toni

What is the FE recipe? And how stinky is it when applied? In a few weeks I'll need to bring these plants inside.

I removed all the scale I could find by hand, then sprayed good with insecticidal soap. (The label said it worked on soft scale, and it was all I had onhand at the time). I will follow up with a really hard jet of water daily for a few weeks, and might try the FE, too. Can't hurt, I suppose.

I guess the key is to get rid of the immature scale babies so they can't latch on and lay eggs. What is the length of the life cycle, anyone know?

I appreciate all advice. I'd like to get rid of these buggers quickly and permanently (and I, too, avoid pesticides and chemicals as much as possible).

I mix the FE 1 tablespoon per gallon of water and spray once a month, early in the morning. I mix it with CocoWet to help it adhere to the foliage. I've heard that a drop of dish liquid will do the same thing as the CocoWet.
Karyn

Buy a bottle of Bayer Shrub and Tree drench and follow the directions - you will have no insect problems for one year - miracle stuff!

Buy a bottle of Bayer Shrub and Tree drench and follow the directions - you will have no insect problems for one year - miracle stuff!

Here is a link that might be useful: Bayer systemic for insect control

Kay, I visited the site and it stated not to use on fruit trees. If you scroll down, the question is asked, CAn I use on Fruit trees and they replied, NO.
I'd stick w/the Fish Emulsion..Just use 1 capful to a 16-20oz sprayer and spray thoroughly. Toni

The local nursery recommended I use horticultural oil, spraying every two weeks.

New, you can use horticultural oil, too..Fish Emulsion works the same way, plus fertilizes the plant..How infested are your trees? Have you applied anything since posting this thread? Toni

First I picked off all of the scale I could find. If the leaves were badly infested, I just cut them off. Then I hooked up my brass hose nozzle and sprayed the trees really hard. Spraying, I figured was a good was to get rid of crawlers, but I could see that it doesn't remove the vital scale since I did find a few more after I sprayed. Still, it is generally the best way I have found to get rid of pests like mites, so I thought it might work on the crawlers. The next day I did spray the trees thoroughly with horitcultural oil. The weather is fairly cool here, and I did it in the afternoon when temps were in the 60's. I checked the trees again today, two days later. I found two more scale that I had missed from my picking, but I believe they were both dead. When I touched them they easily came right off the plant.

I guess my plan now is to repeat the hard water spray every few days, and to spray with horticultural oil one more time in two weeks. At that time I am sure the weather will be cool enough here that I will need to bring my trees indoors. They will go dormant inside, so I am reluctant to spray with FE because I don't really want to fertilize them at this time. I do have a hot/cold hose bib and can easily roll the trees back out onto the deck during the winter to hose them off with water, and I will be sure to do that often. Hopefully that will take care of the problem.

I researched and believe my trees have 'soft brown scale'. But I can't pin down the incubation period for the crawlers. Apparently it varies quite a bit depending on weather etc. So I will definitely have to stay vigilant and keep cleaning off those leaves!

Everyone says scale is a real bugger to get rid of. Has anyone been successful in completely erradicating it? I have about 10 years of experience growing citrus and this is the first time I've encountered scale. I'd prefer it be my last!

I had a very mild scale infestation on one of my citrus trees the beginning of May and treated it with hand picking, hosing off, wiping with alcohol and monthly spraying with fish emulsion. I haven't seen any since but we'll see what happens when they go in the greenhouse at the end of the month. I daresay that scale is the worst followed by spider mites, yuck!
Karyn

New, sounds like you're doing everything possible..Like you, I never wanted to fertilize in winter either, (even though it's not officially winter) but after reading thread after thread where people do fertilize in winter in cold climates, I decided to give my citrus a last feeding, in Oct, of Osmocote and sprayed w/fish emulsion and Superthrive..the FE is really used as an insect preventative. But I'm not going to attempt talking you into doing something you don't want to do. But I honestly don't think spraying the foliage w/FE will harm your citrus, and it's not like you're adding in the soil..

Actually I think the worse bugs are mealy..I can deal w/mites, just a hosing or spraying w/dishsoap and they're gone. Thank God I never had to deal w/leaf miner, and hopefully don't.
I have one olive tree that arrived w/scale..I didn't notice it in the beginning and didn't use anything to rid bugs..Big mistake..before I knew it, the neighboring citrus had scale..but I haven't seen anymore on the citrus, but have on the darn olive. It will get a good spraying of FE soon, whenever it stops raining..and before I put in the gh. I don't want a repeat of last winter. Toni

Ew, I totally have a scale infestation on my lime tree! The people whom I purchased it from said to spray the whole tree w/ rubbing alcohol. This tree is by my desk at the office so I cant really spray any smelly oils or use a hose. It is mainly on the branches, do you think this will work?

Emmajanie I'd take cotton balls saturated in alcohol and thoroughly wipe down the branches and leaves to remove the scale. I don't think that just spraying it will work.
Karyn

I agree w/Karyn..YOu can either use cotton balls or cotton swabs, dip in alcohol, and rid those suckers. I don't think rubbing alcohol odor should be too much of a problem and it's safe..Toni

haha, you know what also works?....I rolled up some duck tape and started dabbing those suckers, they were peeling off like crazy...

Emma, that's a good idea..Toni

Another use for duct tape. I think that's the most versitile product ever made! lol
Karyn

I always thought alcohol would burn a plant's leaves. I'll get out the cotton balls and alcohol and give that a try, too.

If too much rubbing alcohol is applied then it can burn leaves, but if you do it w/cotton balls or Q-tips, then it should be fine. Just like any subtance that is overused problems can arise. Toni

Freaking scale. I haven't had it on my Meyer lemon, but have on bay and Kaffir lime. Finally got rid of it when I repotted everything and sprayed upside-down and right-side up with pyrethrins. I had tried swabbing with alcohol (works great for small infestations) and insecticidal soap (didn't really kill enough of the bugs), and I often fertilize with FE (no visible effect). Isolate, isolate, isolate -- scale really spreads.

If it's heavy infestation on a couple of branches, I'd just prune them off. Then use the insecticides. Ants always accompany the scale on my trees, and dealing with them while you're trying to pick off the scale is a hassle (I have a Myer lemmon too that always seems to get it - never on the grapefruit trees which are right next to it).