Fenbutatin oxide or TORQUE is a professional product produced for the horticultural trade and was designed for the control of Red Spider Mites for ornamental crops under glass. I suspect it has long since been withdrawn for sale in the UK but i have several bags of this powder left after the closure of my nursery in 2005/6. I can say that this product is 100% effective and kills both adults and larvae. It has no (or minimal) systemic action so what is not sprayed is not treated. This product of course is toxic and needs to be handled with the usual health and safety regulations COSHH. I am not going to debate here the biological vs chemical arguments but suffice to say that i spent many thousands of pounds trying to control pests under glass using biological control and failed to prevent damage to plants that were then unsaleable tot he public.
It is simply mixed together with water and applied as a fine spray either using a knapsack sprayer, hand pumped sprayer or mister/fogging device. Please contact me for samples.