> I am starting to do alcohol washes in preparation for late summer > treatment. I washed 3 bee yards today and saw a good bit of variability > with numbers ranging from 0 to 10. The good news is I did not see any > really high numbers. What do you have for comparison? If you have last year's numbers, and your survival was good -- or poor -- that might be a clue. Also benchmarks may be available for your locale. A lot depends on how well the washes were done. I've seen a factor of ten difference between two samples taken in the same hive, one on a patch of actual brood just ready to seal, located in the bottom brood box, and a sample taken on what looked like a reasonable patch of brood comb in the upper box right above that spot, maybe ten inches away. At this time in the north, brood rearing is at its maximum, so most of the mites would not show up in an alcohol wash. Moreover drone rearing is peaking and there will be an explosion in mite numbers as the drones emerge. A lot can happen between now and the end of summer. I do not know your region, but up here I would be expecting trouble by September. As for treating one or all, that depends on your hive numbers and ability or willingness to manage detail and re-test. If using formic, a round of the whole yard would be a good idea as it gets the tracheal mites too, and testing for tracheal is too fiddly for most beekeepers, but they are there with some probability. I seem to recall you use the Amrine board? If so, that is an easy treatment and not too hard on the bees from what I have heard. *********************************************** The BEE-L mailing list is powered by L-Soft's renowned LISTSERV(R) list management software. For more information, go to: http://www.lsoft.com/LISTSERV-powered.html