Tree hive with properties of the hollow tree
The tree hive bears its name due to the reproduced characteristics of hollow trees. In particular, the geometry and the buffering effect of the tree caves are reproduced. One tree hive is equipped with several sensors for temperature and humidity. The current data confirms the way bees reduce moisture.
With regard to the symbiosis with book scorpions, it contains straw areas on the sides of the combs construction. These straw chambers are separated from the bee room by a wide meshed grid, which the bees can easily pass through. The straw is loosely filled, the bees can move and stay in this area. Small segments of wooden boards are bolted to the outer wall in the straw chambers. They serve as a retreat for the book scorpions. IR videos show that book scorpions approach resting bees with preference for parasite checking.
The geometry of the tree hive is based on that of hollow trees. Width x length of the chamber of the bees are 16 x 19cm, the height of the interior 105cm. The ratio of height to diameter is 6 and the bees have a volume of 32l for honeycomb construction. A recent study involving T. Seeley (see downloads) shows a positive influence of small hive volumes on the development of Varroa.
For my current hives, I decided on a construction made of solid wooden planks (4.5 cm) and for additional insulation of the upper half of the beehives made of PUR insulation boards. I will provide future constructions with natural insulation materials.
Breathable construction method
In a modified variant I try to combine the properties of the tree-cave with a breathable construction method. The mass of construction timber has been significantly reduced compared to the previous version. The moisture is partially removed by water vapour diffusion through the lid, using the principle of the diffusion-lid.
In the variant illustrated below, the side thermal insulation was not used.