insulated hive wrap and cloake board stack

 

In Atlanta, cold 20°F temperatures arrived on Christmas Day and the ensemble of 11 arctic oscillation forecast a large negative downturn. I used these metrics as significant evidence that winter temperatures are here to stay.  Since 2010, I have reused my NOD Bee Cozy R8 insulated hive wraps  and believe hive wraps improved the chance of overwintered bee hive survival. As a lazy (aka stubborn) beekeeper and despite warm winter fluctuations, I'll leave the Bee Cozy on till spring 2021.

Photo shows joined hives - overwintered hive below and a March 23rd spring swarm capture above an open Cloake Board. The bee cozy is designed for 10-frame equipment, so it easily slipped over the Bloake Board without removing 8-frame boxes. 

I'm encouraged to see warm moist air (bee respiration) condense outside the hive at the top vent and Cloake Board Entrance. 

Here are current the hive elements:

• screen bottom board with no counting board insert
• NOD Bee Cozy R8 insulated hive wraps surrounding the May 25 hive reorganization
• inner cover with top notch up ventilation
• two 3/4 inch sheets of XPS foam board insulation between inner cover and telescoping cover
• white corrugated plastic sheet overhang
• concrete pavers on top

condensation on cloake board

52 °F and there's a puddle of something on the cloake board landing area.  I dip my finger into the liquid and confirm the taste of simple water - nothing sweet about it.  Stacking the medium sized swarm atop an overwintered hive creates enough combined warm moist respiration to create condensation. Condensation, common in winter has taken me by surprise in spring.

2019 Bee Cozy

Ants create tunnels and nest in the extruded polystyrene foam boards in warmer weather, so I postponed insulating the hives until now. In Atlanta, first frost arrived on November 12th which is just on the early side of historical average.  November 12 also marked the first subtle Arctic Oscillation downturn this winter.

Here are current the hive elements:

• screen bottom board with no counting board insert
• bee cozy hive wrap surrounding the August hive down-sizing
• inner cover with notch up ventilation
• two 3/4 inch sheets of XPS foam board insulation between inner cover and telescoping cover
• white corrugated plastic sheet overhang
• concrete bricks on top

bee respiration with and without Bee Cozy

Here I'll compare winter bee respiration with and without the Bee Cozy hive wrap for two hives.  On the graph, think of the horizontal axis as outdoor temperature and vertical axis as the bee respiration temperature.  See previous posts for the measurement method.  All graph points have top vent temperatures greater than paver temperatures which is consistent with an active and alive hive. Red circles without fill are measurements with no Bee Cozy.

In the graph notice:

• all points are consistently closer to the upper left corner with the Bee Cozy
• hive #1 has top vent temperatures as large as 80 ℉ and consistently warmer than hive #2
• the last measurement (blue circle with fill) is consistently closer to the upper left corner than other graph points.  

Hive #1 has more flight activity than hive #2 and the last measurement (blue circle with fill) is most likely attributed to a larger bee population in response to spring forage and warmer spring temperatures.

with and without Bee Cozy hive wrap

There's no ideal way to compare winter bee respiration with and without the Bee Cozy, but I'll do my best here.

IR temperature measurements started on 12-Nov-2017 without the Bee Cozy.  See a previous post, bee respiration, for measurement method.  On 2-Jan-2018, the 17.0°F outdoor temperature convinced me to add the Bee Cozy to two vertically stacked hives.  Only the queen excluder portion of a cloake board separate these hives.  1 Bee Cozy is added to the bottom hive (4 boxes) and 2 overlapping Bee Cozys are added to the top hive (5 boxes). The Bee Cozy is designed for 10 frame equipment.  So, the Bee Cozy easily slips over my 8 frame boxes and cloake board with no effort.  This 2-Jan-2018 measurement point appears as a blue dot in the lower left corner of dots - Paver temperature equals 17.0°F and Top Vent temperature equals 31.0°F.  On the graph, think of the horizontal axis as outdoor temperature and vertical axis as the bee respiration temperature.

All graph points lie above the green line (x= y) which is consistent with an active and alive hive. Blue dots are measurements without the Bee Cozy and trend beneath orange dots which are measurements with the Bee Cozy.  Excluding a few points, the Bee Cozy consistently increases bee respiration (Top Vent) temperature.

Wondering why I went into winter with such a tall stack of boxes which requires step ladder beekeeping - there's no good reason other than lazy beekeeping.

bomb cyclone

Winter storm Grayson brought cold temperatures to Atlanta, but no snow.  Use this link to see NOAA's satellite image.

Here's a photo of the upside down telescoping cover.  Warm moist bee respiration which left the inner cover notch, condenses on the cold telescoping cover and froze as a white ring.  Click the image for more detail.

17 °F temperatures encouraged me to add the bee cozy hive wrap now.    The hive wrap is designed for 10 frame equipment, so easily slips over my 8 frame boxes and cloake board.   I'm overwintering a tall vertical double stack of hives.   The stack contains a cloake board, where I removed the cloake board's sliding floor leaving its queen excluder to separate the two hives.  I added two overlapping cozys on the upper large stack of boxes and one cozy to cover the smaller lower stack of boxes.

From the bottom up, here are the hive elements at this time.

• screen bottom board with counting board insert removed
• 1 bee cozy hive wrap surrounding 1 deep box and 3 medium boxes 
• cloake board with integrated queen excluder and sliding floor removed
• 2 overlapping bee cozy hive wraps surrounding 2 deep boxes and 3 medium boxes
• inner cover with top notch ventilation
• two sheets of 3/4 inch XPS insulation 
• telescoping cover
• white corrugated plastic sheet overhang
• concrete pavers on top