Yup. Scale is a tough one. You need to understand its life cycle in order to effectively combat it. I suggest using The Google and finding a suitable pamphlet from an Extension Agency you like and go from there. Soaps and oils work, but timing is everything.

Good luck.

Dan

Insecticidal Soap is not a control for cottony cushion scale although oil is. Usualy dormant oils will work by coating the scale so they cannot breath and they then suffocate. If needed a superior oil, or summer oil, can be sprayed but due care is necessary because even this oil could harm the shrub.

Insecticidal Soap is not a control for cottony cushion scale

Sure it is.

Soaps work on the crawlers.

Not as well nor as easy as sticky traps for crawlers, but presumably the OP has the soap already.

Dan

we know them as mealy bugs and over here if we get them on our plants we look for ants as they have a symbiotic relationship. also our treatment is after dealing with the ants we use a product called "white oil" it is a product of the petro-chemical inustry what i think you call dormant oil?

there is a homemade recipe on our remedies page. the oil should be applied after the heat of the sun and may need subsequent doses of up to 2 extra applications at say weekly intervels.

if they are in shrubs an applicatin of vaseline (anoterh petro chemical product) or some such gel product around the stem will stop the ants crawling up the bush, be sure that the foliage does not make contact with any other avenue that the ant may use.

scale insect is treated the same way it looks more like hard little pimples on the branches and backs of leaves.

len

Here is a link that might be useful: lens garden page

I have one orange tree in a container that came from the nursery with scale. It was at one point massively infested with scale (but not the cottony cushion scale per se), and I use an OMRI certified product called "Organocide." It' a fish/sesame oil based product that works on all soft bodied pests. Stinks to high heaven. But it works. It's also about $18 a bottle, so might get expensive for a larger tree. Good luck. I hate scale!