A most common pest found in greenhouses, two of them called Boisduval scale, and, Brown scale, are mostly found on orchids; neither is difficult to control, altho the dead ones remain on the plants and look as bad as the live ones, so they should be brushed off with an old toothbrush; all parts of the plant must be sprayed frequently with any control; use Metasystox R, Malathion 50%, or Summer Oil Emulsion out-doors. F87-180
Cygon is best for Boisduval scale on cattleyas but it has not been labelled for such because of the expense involved in getting official authorization. A87-615; 946
Scale has a ten-day life cycle, so a contact spray must be applied every ten days to combat it, for three consecutive applications; Cygon 2E is recommended as a drench. OIE85Jy-4