Question
Hi, We have to two sagos with the white scale you mentioned before in
response to a question in 2007 that have also turned yellow.  
I read the previous answer about treating with Horticultural oil and then even
to do an insecticidal drench. Our sagos have a border of begonias. Are there
any safe horticultural oils you recommend for the Houston area that are also
safe for the begonias and what do you recommend for the insecticidal
drench. Any help will be appreciated.

Answer
Hi Janet, try to find an oil called "ultra-fine oil" , make sure you apply it per instructions during the latter part of the day, when the sun isn't that hot, because it can act as a magnifier for the suns heat, and that is detrimental, apply it late afternoon and let it work on the scale overnight, then spray it off, along with the dead scale the next morning, this is a control, not a cure, and needs to be repeated periodically. The drench is put out by "Bayer" it comes also in a concentrate, it is in a quart container, blue in color, this is only effective when the sago is actively growing, sending out new growth, for it needs to take the product up into its system, so that the scale dies when it feeds on the sago. The oil is safe around the Begonias, just be careful not to spray any on the Begonias themselves. When using the oil, be sure to add a "sticker", they sell several different brands, this will assist the oil in adhering to the scale and suffocating the little terrors. This is a persistent pest! and here in Florida, the majority of Sagos are gone because of it, people just give up because of the difficulty and effort required. Nick