In most parts of Oregon, July brings the end of the nectar flow and the beginning of dearth. A few timely actions taken by a proactive beekeeper can do wonders to relieve colony stress and increase a colony’s likelihood of surviving the winter.
The end of the nectar flow means bees will not be drawing out wax or bringing in loads of wet nectar to cure. If you haven’t already started consolidating frames, do so now by rearranging honey supers where possible. Remove empty and nearly empty frames so that the remaining boxes are filled with full ones.
By the end of July you should be ready to harvest honey. If this seems early, keep in mind that most colonies don’t gain much harvestable weight after the end of this month.
More importantly, your bees will fare much better in the seasons to come if you can get any needed Varroa mite treatments done before mid-August. If you can knock the mite levels down at the beginning of the beekeeping new year (August 1), your current bee population can foster a generation of well-nourished bees that have not been compromised by mite infestations and mite treatments. The workers will have longer lifespans and should be more resilient to the stresses of winter, the winter brood will be healthier, and even the spring bees will benefit from lower mite numbers at the start of brood-rearing season.
Before treating for mites, it is important to do a mite count. A powdered sugar shake or alcohol wash can both give accurate results. You can also use the sticky board method. There is an excellent video on how to sample mites posted on the Oregon State University Extension Service YouTube page.
A colony going into winter with high mite numbers is unlikely to survive. Many beekeepers are opting to treat for mites in fall when they count 3–6 mites per 300 bees, or a 1–2% rate of infestation. Colonies with counts even a little higher than that often appear to collapse from thriving hive to deadout in just a few weeks come August, September, or October.
Before choosing your treatment, consider factors such as: temperature, time available to treat, and the use of previous treatments. Formic acid, while effective and safe to use with honey supers on, can sometimes cause queen loss and other problems in high temperatures. Other treatments, such as synthetics and essential oil formulations, require that honey supers be removed before use. If your colony is missing brood due to a queen issue or swarm, it is advisable to do an oxalic acid treatment during the broodless period. See the documents section of the Oregon Master Beekeeper website for a handy breakdown of the pros and cons of the most common Varroa mite treatments. It is important to always follow the manufacturer’s instructions when using any treatment. Failure to do so could harm your bees, compromise your health, or, in some cases, risk an increase in mite resistance to the treatment method.
More Tips for July:
The end of the nectar flow signals the beginning of robbing season. Vulnerable colonies can be plundered in a matter of days, and robbing also transmits Varroa and disease. To prevent problems, don’t spill honey or nectar near your colonies nor keep them open any longer than you absolutely must. Cover open boxes and frames to prevent easy access. Reduce entrances on weak colonies and keep a robbing screen handy, just in case.
Speaking of weak colonies, consider combining them with stronger hives if you can determine they aren’t afflicted with Varroa or disease. Whenever possible, you want to “take your losses” in late summer and early fall instead of in the winter.
Continue supplying water for your bees if there isn’t a dependable source available. This will keep your colonies from drawing the ire of birdbath watchers and swimming pool owners. A Honey Bee Biology article written by Dr. Wyatt Mangum and published to the American Bee Journal explains that keeping a nearby water source can also make a big difference for the hive; if a honey bee must fly a long distance to the water source she is able to carry less water. For water carriers making an average of 50 round trips a day, this small difference can really add up over the course of the season.
Ensure your colonies are queenright while queens are still available.
Don’t forget to leave plenty of honey for the bees when you’re removing honey supers. Colonies in many parts of Oregon will need 80–100 pounds of honey to get through the winter.