At the same time I enlisted the help of a customer of ours, he was about to add Apistan to his regular hives and agreed to a drop test for us. Using a hive which had no treatment after May 24th, when the Apistan strips were removed, two strips were added and a tray inserted for 24 hours. The results were truly astounding, the tray was black with Varroa, thousands and thousands, just incredible amounts.
Over the years we have heard of hives failing to make it through the winter even with Apistan strips in. Having seen the amounts of Varroa on those drop tests I can see why the damage to the bees must be considerable at a time when new undamaged bees would be hard to come by. Bees emerging in the late summer, early fall, will go through the winter into early spring, it stands to reason that Varroa damaged bees are unlikely to make it, leading to winter hive death.
We dispensed with the tobacco fairly early on in the season, even though it appeared to be of benefit during our manipulations. As an ex-smoker we found the smell to be very offensive, it clung to clothes and the vehicles smelled all the time of tobacco.
The use of essential oil combined with FGMO has definitely shown promise in our first attempt. The volume of Varroa is low, damage to the bees is visually insignificant, the overall health of the hives is excellent.
On looking back and studying my notes I must confess that I could have been more diligent in the application of the FGMO but pressures and priorities can throw havoc into good intentions.
Today I found some Varroa damaged bees, small and wingless. This from a hive that was angry and marked for re-queening, on checking for satisfactory queen acceptance I noticed a number of damaged bees. From last years experience of angry bees robbing out dying hives and returning with massive infestations of Varroa, I can only surmise that this hive is suffering from the same problem. Hopefully, we have caught it in time and with a new queen and treatment, it can be saved.
A word of warning!
There is nothing to be achieved in visually looking for Varroa, you cannot see it on the bees if you can then the volume of Varroa is reaching critical amounts.
We are now wrapping up our queen rearing for the year, and dismantling our baby nucs used for queen rearing. These hives have been used all summer long raising and mating queen cells to laying queens and were treated with FGMO every time a queen was harvested. As the new cell was introduced a quick squirt of FGMO was run across all the frame tops. The interesting point, there is no signs of Varroa whatsoever! These are disposable units with a few hundred bees, at the season end, the brood is allowed to emerge and then all bees are removed to a larger hive. On extensive examination, there are no signs of Varroa. The roof of the cells have been examined under a large magnifying lens and there are no signs of Varroa faeces normally seen after emerging brood.
Varroa left untreated will kill hives, eventually. Subject to a variety of circumstances, sometimes quickly, occasionally over a period of years. Essential oil does minimise Varroa in the early spring. FGMO will help in keeping numbers in check, until the hive becomes large, by that I mean 3 deep brood boxes, at which stage the treatment becomes diluted by the sheer volume of bees. My thinking at that point would be to either increase the dosage or the number of treatments per week.
Where to from here?
I have already succumbed to Apistan again this year. The loss of hives last year, the amount of time spent this year cleaning up dead outs was devastating and an economic disaster, we cannot afford to go through that again.
Finally, I personally believe that is helpful in our control methods, I fully intend to use it next season with wintergreen in the early spring, but this time I shall be more diligent in its application in the hope of eliminating Apistan and Formic Acid.
I wrote the above articles some years ago and while my methodology has changed just slightly, the results are still the same. It is now fall 2001, we are putting the bees to bed for the winter and without qualms as to their ability to winter over. On sampling for Varroa we find only small samples, certainly not the massive infestations first found when Varroa came into our area, which devastated our hives. We do not use harsh chemicals nor have we used formic acid, we have managed to avoid that particular pitfall and our bees are healthy. Apistan is still part of our regime, but only because our livelihood depends on bees, if I was a little braver, then I am convinced it would be possible to manage without it.
After a great deal of observation and discussion I have come to the conclusion that once the initial infestation has gone, and all feral hives have died, that area of re-infestation is over. Having watched some of the hives we used to have, coming home laden with Varroa caused by their robbing habits, those days are gone. Thank goodness. So, if one treats with a variety of treatments, giving it, it’s fancy title ‘integrated pest management’, then coping with Varroa isn’t the dangerous problem we were lead to believe. This is not to make light of a serious problem, but only to reassure, we can keep bees with Varroa in the hives.