Oil emulsion sprays will give you effective control if applied early in the morning on days when the temperatures are mild (45-85 F). Systemic insecticides like Cygon and Orthene can also control tea scale. Contact insecticides like Malathion, Dursban and Sevin are very effective but repeat applications may be necessary. I suggest applying two types of controls (read the label and make sure that the active ingredient is different) so the scale insects will not get used to applications of a single insecticide.

Luis, you've mentioned some exceedingly toxic pesticides that have been pulled from the market for private use. Cygon has been out for several years, and Dursban followed soon after. I believe that you can still obtain Orthene, but probably not for long.

I have had good luck with dusting the leaves, especially the undersides, with dusting sulphur. It is an old, but effective, remedy. Good luck!
fireflyintexas

I am having a HORRIBLE problem with tea scale on a particular camellia. It is really crippling the plant. Can anyone specify a certain brand of insecticide to get the job done? I am at my wits end with applying stuff (spray on stuff) that appears to be totally ineffective.

Dan

Camellia tea scale is a difficult insect to control once it's taken hold. I have found all-season oil sprays work the best, but you have to spray until you see no more white. That may mean putting on a rain suit and getting a hose-end sprayer. Ortho makes a great one that you just pour the oil in, set the dial and go. No measuring required. You have to spray on the underside until the oil penetrates the scale. Also several applications may need to be applied and once it's under control you can spray seasonally spring and fall when insects are in crawler stages works well too.

I had a plant about 6' tall that was so badly infested with scale that I just had to prune it severely then started spraying and it's now under control and beautiful.