Malathion is strong stuff and is not my first choice and I can even add that it appears inaffective to a small scale type that is tan/red in color and very dense in population,having no squishy innards to indicate life.They are flat and dry,overlapping and cause severe discoloration to leaves.I have them attacking an apidestra and rhapsis palms.I have tried everything to eliminate them,but they just come back,even afer repeated applications of everything under the sun as well as cutting the apidestra down to the ground.The Malathion did work very well on traditional scale and succeeded where other,less toxic remedies failed.I did have to use it a few times and as these plants will be used in my chameleon enclosures,I did not want this to be my first choice.It is not systemic and with a few good rinsings in warm/soapy water and a week or so outside to air out,I would expect it to be safe.I reiterate what Toni said about it harming the gardenias.Some plants do have a marked sensitivity to it.It has burned or blanched some leaves on the rhapsis palms and a draceana,but these will regrow to cover the damage.Scales are most prolific on stressed trees and plants,keeping plants in the best possible conditions, should help to avoid the scale.Adult scale do not find their way back tot he tree, if knocked or scraped off.Even if they did,scraping them off usually breaks the proboscis they feed with an dthey would starve.The adults are more or less something to wait out,the crawlers(moblile stage of the scale) is what you are really after with spraying and that is why reapplication is needed.The adults die off on their own in a while,if you can kill the new generation before they take hold,you are winning the battle.I HATE SCALE!!!

Thanks to everyone here for all the great advise! Here's a company called Woodworker's Supply (woodworkers.com) website I found to purchase three types food-safe finishes. I also checked the John Boos Company which manufactures both residential and commercial butcher block and wood countertops and cutting boards for prices on their Mystery Oil and Boos Cream which combines mineral oil and beeswax, which is rather expensive, but the website has a lot of helpful information in their FAQ section. GENERAL FINISHES AND BEHLEN Salad Bowl Finish are formulated to create a non-toxic, food safe finish coating. Apply to raw wood, allow 6 hours dry time before recoating, then wait 72 hours prior to use. Pint, quart or gallon cans. Preserve™ contains a blend of oils from the meats of exotic nuts. Immediately safe upon application (made without toxic driers or solvents). 8 oz. squeeze bottle. Clapham's Beeswax Salad Bowl Finish is made with natural beeswax with oil and is perfect for use on cutting boards, cheese boards, fruit or salad bowls, toys, utensils and more. Ready for use immediately after application. Buffs to an elegant shine once it dries. 8 oz. container. http://woodworker.com/gen-fin-salad-bowl-finish-mssu-107-279.asp

I'd always reach for the dedicated horticultural item. Manufacturers of household items routinely switch formulations depending on what supply is cheaper. Horticultural applications will be the same from one jug to the next and from one year to the next-unless specifically spelled out. Just a s Dawn for Dishes might work just as well as the actual insecticidal soap, it might not and could cause phytotoxicity-damage to the very plant(s) you're trying to protect. I'd strongly urge you to only use actual horticultural products. +om

Thanks for the feedback, everyone! I'm sure the effects are also highly dependent on the strength of the emulsion. I will say this about horticultural oil, though... it doesn't cause post-spray stinkiness like neem does! I think I have a new go-to during the winter months when I have to co-exist with my trees indoors. I'll probably fall back to neem in the summer months. -Tom