On Wed, 3 May 2000 13:16:43 -0500, Blane White, MN Dept of Agriculture, [log in to unmask] wrote: >I have a couple of comments on Don's method. It is actually a > method developed not by Don but by researchers at USDA. By > dissolving the menthol in vegetable oil the surface area is > greatly increased thereby greatly increasing the evaporation > rate in cooler weather. Yes it does work if done properly > and yes it is legal since the applicator is using less that > the menthol label calls for ( you can always use less than > label rates legally, never more than label rates On Mon, 26 Mar 2001 14:07:23 -0700, George Richtmeyer [[log in to unmask]] wrote: > Tracheal mites are a roll of shop towels soaked in a quart > of canola oil and 1oz. of peppermint spirits. I've been impressed by the anecdotes I've heard about the blue shop towel method. I did a little trial of making up the treatment last Saturday (pictures at http://www.internode.net/HoneyBee/diary/ for March 24th) and we intend to use it this spring, even though we did treat last fall with 3 pads of formic. (Yup we still have some bees, but everything is for sale - See http://www.internode.net/HoneyBee/Sale/). In reading about the blue shop towel treatment, I notice that some people decrease the amount of menthol in the dose from the 50/50 oil-to-menthol ratio that is mentioned in the original article cited earlier here on BEE-L by bob (Feb 97 ABJ). In the second quote above, the writer has reduced the menthol to 1 part menthol in about 28 parts of oil if I calculated correctly, and is the lowest dose I've heard so far. Menthol spirits are mentioned, not crystals, so am I correct in therefore assuming an even lower menthol level? I've also noticed that some people use canola oil and others use vegetable shortening. The ABJ article speaks of 'two pounds of canola oil' and two pounds of crystals. Now liquid oil is usually sold by liquid measure (ounces, ml, cups, litres, quarts, etc.), not pounds, and and the solid form known hereabouts as shortening *is* sold by pounds, so the meaning is not entirely clear. The same word may have different meanings in differernt localities, so I'm hoping someone(s) can set us straight about this -- if it matters. My conclusion from reading is that the dose in the ABJ article is a bit on the high side. When we made the sample up, I cut the roll into three, since I was afraid that I might kill some brood as mentioned in the same article if a half sheet is used. I've also wondered if the second dose is necessary. Has anyone actually measured before and after and determined the optimal dose, or has everyone just used his or her own version of the treatment and not confirmed the efficacy or necessary doses by measurement? And, if the USDA did develop the treatment, is it written up somewhere? allen http://www.internode.net/HoneyBee/ --- Onward through the fog.