October will be arriving next week and summer is now officially over. Out in the fields only a few flowers of the aster family are still in bloom. The first frost is not far off and will kill this last remaining pollen and nectar source.
I looked into several hives and nucs last weekend. The queens have severely cut back on raising of brood although there were still small patches of capped brood, open brood, and eggs. With the decline in both nectar and pollen coming into the hive, northern queens will soon stop all laying. Some queens of Italian stock may continue laying throughout the winter, but a slower pace.
The stopping of brood rearing provides an ideal time to do a last mite treatment for the year. By late October all brood should have emerged; along with all varroa mites hidden in the capped cells. With no mites hidden inside brood cells this provides the ideal time to apply an oxalic vapor treatment to kill phoretic mites and leave the hive relatively mite free throughout the winter.
The daily high temperatures and nighttime low temperatures are also declining. These lower temperatures will cool any feed being offered to the bees. The bees will not take in cold syrup and, as a consequence, the hours per day when the feed is warm enough for the bees to eat is greatly shortened. Hopefully you have already completed any fall feeding you were planning.
Any weak hives should have been combined in September as recommended by previous articles in this blog.
On the few warm days ahead the bees will be propolyzing the cracks and minor holes in the hive. This is done to prevent winter winds from gaining access to the hive. After October 1st do not split the upper and lower brood chambers. This will break the propolis seal between the boxes and the bees may not be able to repair the damage.
For those beekeepers that approach beekeeping from a more scientific basis it is a good idea to understand the strength of each hive. Strong hives tend to survive winter better. By raising the inner cover for a few seconds you can visually determine the colony strength. Simply count the gaps between frames that are filled with bees. Eight to ten frames (8-10) with bees are considered strong hives. Less than five (5) frames are considered weak. Ideally, all of your hives will be strong.
The next thing to consider is how you will limit moisture build up in the hive during winter. Moisture is generated by the bees when they eat and metabolize their stored honey. You should be incorporating moisture control methods now; not in the middle of winter. You can either let natural air movement vent any moisture from the hive or you can incorporate some type of moisture trap into the top of the hive. Everyone knows that warm air rises. This air movement will take any moisture from the hive if you provide an air escape hole high in the hive. Some beekeepers simply drill a one inch diameter hole below the hand hold recess in the upper brood chamber. This hole is left open throughout the winter. It also provides a secondary exit if the lower entrance becomes blocked by snow. (This is the method the author uses with good success.) Other beekeepers modify the inner cover and add a ¼ inch deep by one inch wide notch in the edge of the inner cover. The notch is positioned down against the top of the upper brood chamber. (Inner covers with the notch already present are available commercially.) Both methods work. If you don’t want to put holes in your equipment, then you need to add a moisture trap below the inner cover. The moisture trap can be wood chips or shredded paper suspended above a screen, or a commercially available moisture board.
Here is an example of the moisture vent hole drilled below the hand hold cutout. It also acts as a winter emergency exit.
Here is a moisture vent cut into the inner cover. The vent is placed downwards against the top of the brood chamber. It also acts as an emergency exit if NOT covered by the outer cover rim.
The weather is still to warm to contemplate adding winter wraps or providing winter feeding,. Winter wrapping is usually done in late October. The pros and cons of wrapping your hives will be discussed in the next post and probably at the next club meeting. As will the providing of emergency winter feed.