Sunday, November 3, 2013

Fall Inspections: Wrapping hives and installing mouse guards

The home apiary before wrapping (with foam between the inner cover and the telescoping cover)

The home apiary after wrapping (The nuc on the left is wrapped by itself. All the other nucs are wrapped in pairs. I am curious to see how this nuc does in the spring.)

 I spent this weekend wrapping my hives.

Couple years ago, I made two home-made hive cozies. They slip right over the hive on the stand. You can also remove the "roof" and get into the hive without having to pull the entire "cozy" off. They are perfect if you only have a couple of hives. However, they are way too bulky to store in the summer. You can see them on the "after" picture.

All the other hives got 1 piece of foam between the inner cover and the telescoping cover. I used 1" thick rigid pink insulation foam. I also put 4 pieces of that foam so that they completely enclose the hive, except for the bottom board and 3/8" right above it. As you can see on the picture, I used some pieces of duct tape to hold the pieces of foam in place until I was able to tighten the strap. I will remove those pieces of tape later, when I install the candy boards. I also wrapped duct tape completely around the top and bottom of the hive in case the strap fails:

Double deep hives, fully insulated
The duct tape goes completely around and ends up on itself, since sometimes when it is cold (as it was yesterday) it does not stick on the foam.

For a strap, I used a 1" x 6' cam buckle strap. I prefer those instead of ratchet straps as they don't seize after being exposed to the cold and rain all winter. Of course, of you have more hives, either one of those straps may not be practical. A simple spool of 1" webbing and a trucker's knot will accomplish the same at a fraction of the cost.

So, what is the purpose of wrapping hives? After all, bees have made it without wrapping for millions of years.

I wrap because it stabilizes the brood nest temperature and reduces condensation.

If you ever had a strong hive and not-so-strong hive side by side, you probably noticed that the stronger colony starts to forage earlier and finishes foraging later than the weaker colony. This is because the stronger colony has more foragers to spare. Adding insulation to a colony also allows it to send out more bees as foragers. It reduces the temperature swings between the daytime high and the nighttime low. With insulation, a honey bee colony needs less nurse bees to maintain the brood nest temperature. In this way, an insulated honey bee colony can resume brood rearing earlier in the spring than a non-insulated one. It can also make the most of the first pollen flows (maple and willow here in NW Ohio) that usually happen during marginal flight weather. An insulated colony will usually be 2 weeks ahead as far as population and brood rearing are concerned compared to a non-insulated colony.

An added benefit of insulating your colonies is that the insulation dramatically reduces condensation on the roof and sides of the honey bee hive. As you probably know, moisture in the winter kills bees. Sometimes, moisture in the hive is introduced by uncured syrup, especially if you had to feed late in the fall and the bees did not have time to cure and cap the syrup.

Moisture is also introduced through the metabolic processes of the cluster itself and the conversion of honey into heat by the honey bees. If the top of the hive is not insulated, the warm and moist bee breath forms condensation droplets right above the cluster. The resulting water droplets can drip on the clustered bees and quickly chill and kill them. Adding insulation overhead as well as gently tilting the hive towards the entrance alleviates that.

Of course, once the bee hive gets cozier due to the added insulation, a slew of other critters want to make it their home, too. The most destructive are the field mice.
A single deep hive box with mouse guard and 3 3/8" holes on the left
You probably haven't seen any traces of mice in your apiary. Mice are tricky. They usually invade the hives once the bees start clustering consistently. Then they can make their nests at leisure, often destroying the entire bottom box by chewing through the frames and foundation. If the weather warms up unexpectedly for the mouse, the bees will kill it and completely propolise the body.

I always recommend putting mouse guards on. They are quick and easy to install and can save the beekeeper a lot of grief in the spring. You can make them from 1/4" pet fencing. This year, I used drywall corner (available in all home improvement type stores) that I cut to size and drilled 3/8" access holes. If you use a wood block while you are drilling, your holes will be clean and won't have burrs and sharp edges that can damage the honey bees wings.

This blog post is getting quite long. I will finish it next week with pictures and recipe for my candy board. I will also talk about upper entrances for winter. Meanwhile you can tell me in the comments how you insulate your hives. Did you insulate already and if not when do you plan to do it?