The Mite Fright (and Fight).
The image above is the last yard we harvested in 2019, and we always give a mite treatment on the day of harvest. It's a time when the hives are already open, and it's essential to get the sequence underway as quickly as possible in late summer. These particular hives were all singles that weren't distributed until late June, so their mite load isn't as scary as some other locations with mature hives harvested in September.
During harvest season I keep an extremely close eye on the drone brood that is exposed when boxes are pulled apart during honey collection. Every year there is a potential mite explosion preceded by drone larvae loaded up with multiple mites. This is also why we moved up our treatment schedule to very early August. We don't really want to see the image below at all, but if we do, then we know we must handle the mites instantly or expect over half of the hives in the location to crash (die) before winter arrives. If those mites in the horrifically infested round of drone brood are permitted to hit the worker population with full force, the hive is pretty much toast. On top of hive mortality, some of the surviving bees will wander over to nearby hives, bearing their mites, and compromise the neighbors as well. A vicious cycle indeed.
We've worked exceptionally hard to stay on top of the parasite load this year since we're planning to send bees for California almonds again this winter. We want to do our very best to send strong bees that are worth shipping, make grade for pollination fees, and return busting with bees. The two keys are low mite loads and adequate feed. Those two topics go hand in hand right now in the fall beekeeping schedule.
Since our mites are now well under control in the vast majority of the hives, we are inducing another round of brood rearing to stimulate a strong population of young bees that have not been parasitized. While the late summer flowers actually yielded nectar and pollen at levels much better than the past three years, there is not much for the bees to collect at this point. As a result, brood rearing greatly declined over the past two weeks. An extended forecast with highs struggling to hit 60F will demolish egg laying rates without some kind of stimulus. This year we're using the brood builder patties from Dadant. I like that they're a little thinner than some other patties and fit under my rimmed lids with room for bees to get at them from both sides.
And another sign that fall has arrived? Here is a bottom board covered with drones being driven off the combs. Sorry boys, the end is nigh!
Overall the bees look quite good right now, though there is more rain than I'd prefer in the forecast. We have two more rounds before I'll feel like the bees are shipshape, and then if everything remains on track we'll have the great bee roundup and send them west.