Temperature Monitoring – 25mm Hoop vs 50mm Cypress

Disclaimer – It’s really hard to compare boxes because there’s so many variables – Probe position, yard position, sun vs shade, roof vs no roof, thickness, densities, size, colony strength, colour, the list is endless. To make a better comparison we’ll need to have multiple boxes of each design being tested over years.

As far as I know there’s no research or data comparing native bee boxes so there’s no proof any box design is better than another one. If you see anyone claiming a box has better insulation I’d ask for data and information about how it was done.

The Goal – To get sensors in multiple boxes of each design to be able to confirm results. We’ll need to test brood temperatures, Honey pot temperatures, sun vs shade, summer vs winter.

Observations so far?

August 2024: From the tests I’ve done so far I’ve made some basic observations. Some might be obvious, some might be surprising. I still haven’t seen any evidence to suggest a 50mm cypress box is any better than a 25mm hoop pine box.

Summer:

The hoop pine box warms up quicker and loses heat quicker compared to the cypress box
The darker colour of the clear coated cypress, the density of it and the size of the box could make it hot in summer compared to the hoop pine box
The hoop pine box painted a light colour seems to max out at a lower temperature in full sun in summer compared to the cypress box
The cypress box could be painted white to lower the temperature in summer but then it would be even colder in winter

Winter:

Generally in winter the cypress box could be cooler than the hoop pine box
The size/density/mass of the 50mm cypress box takes longer to warm up in winter. Because of this it may not get as warm as the hoop pine box (full sun exposure)
If the cypress box was in full shade it could be a problem as the box may stay cool. This is ok for most areas but could be more critical in extreme areas.
Generally in winter the brood reduces in size, possibly removing the probe from the brood and also the smaller brood can be a lower temperature.

Box designs and Variables

I’m comparing two boxes I have made, a standard design 25mm Hoop Pine OATH and a 50mm Cypress box of the same internal volume. I’ll try to make sure the two boxes are always of similar position with equal sun and weather exposure, equal colony strength and will have to check probe position occasionally.

I occasionally check probe position to make sure it’s in the brood.

Temperature Charts: 25mm Hoop Pine Boxes vs 50mm Cypress Boxes

January 2023 – Summer

February 2023

Chart below: The 50mm Cypress box takes longer to warm up and then longer to cool down, losing heat slower.

March 2023

April 2023

Chart below: I’ve added extra probes to the honey pot areas. The honey pot probe is placed in the rear corner of the box.

Chart below: Chart is the same as above with the addition of two other colonies, just for comparison. Colony 4 is in the shade.

May 2023

Chart below: Honey pot temperatures are pretty similar for the 25mm and 50mm boxes

Chart below: This is the same chart as above with another two colonies added for comparison.

June 2023 – Winter

Chart below: I moved the test boxes to Pine Mountain Qld (near Amberely), a colder area for winter 2023. Brood temperature differences could be explained by probe position. As per previous charts, the honey pot temperatures show that the 50mm Cypress box takes longer to heat up and longer to cool down. There’s even a big difference between colony 1 and 4 which are both 25mm hoop pine which shows that we need multiple boxes of each type in the tests.

July 2023 – Winter

Chart below: This chart shows three colonies. 2 colonies in 25mm thick boxes and 1 colony in the 50mm thick Cypress box. All boxes are in full sun all day with roofs.

So far I don’t think you could make any claims that one box is better than other one?

Differences in brood temperatures could be explained by probe position. The honey pot temperatures might be a more accurate measure of box performance. The honey pot temperatures are very similar between the 25mm hoop pine and 50mm cypress.

I only had temperature probes in the brood for the summer tests so it will be interesting to see the added honey pot temperatures in summer.

August 2023

Time to check the boxes and probe positions.

Photos:

Colony 4 (green line) in the charts is a 25mm hoop pine box. As suspected the probe was on the edge of the brood giving a lower temperature ready.
50mm cypress box from the charts, as suspected the probe was close to the edge giving an inconsistent reading. As the brood increased in size for summer it was getting good reading but as the brood reduced in size over winter the readings were inconsistent.
I’ve added another 50mm cypress box and a 12mm Ply wood box to the test group