Copper Soaps: what orchids should it be used on

[cluelessmidwesterner]

Thanks everyone.

Roberta this Oncidium has had scale since I purchased it a year ago. I've total changed the media, used insecticidal soap, spot treated with alcohol as soon as I see them but the little blighters keep coming back. Because of the scale I have a lot of leaf spotting. I know some Oncidiums do have leaf spotting but it could be due to fungus.

I'm a bit leery about using systemic product because 1. it's in s/h and 2. my resident felines occasionally get at my orchids and if I don't catch them in time will "graze" on the leaves.