Bugs

[gngrhill]

Hi, all. I have been growing orchids now for almost 3 years and have never had insects except for fungus gnats which I control with a mosquito dunk floating in my watering water. Does a terrific job on them. Last week I found what I'm sure was a mealy bug on the bloom stem of one orchid. I hand picked it off and haven't seen another so far. Today I found on a different orchid a lot of small brown bumps which I am thinking might be scale, but never having it before am not sure. I wiped the leaves with alcohol making sure I got them all off. What I would like to know is where do they come from on orchids that have been here for a year or two and none of the others seem to have them ? They must come from somewhere. All the newer orchids seem to be clean. Have not seen any other bugs except these 2 and they have been here, never outside. Any ideas ? Do you think my treatment is ok or do I need to do more ?