Sealey " ... inspected 49 entrances in 33 nests. Knotholes (56%), tree cracks (32%) and holes among roots (12%) formed entrances. Most nests (79 %) had one entrance. The others (21%) had up to 5 entrance holes."
What Sealey did do (in 'The Nest of the Honey Bee', Sealey and Morse, 1976), was to present an idealised diagram of a tree nest, which many people have subsequently erroneously assumed to be some kind of blueprint from which to design beehives.
Sealey writes: "Nest entrances tended to be near the nest bottom. (29 entrances from 20 nests)(*). This predominance of bottom entrances is highly improbable (P <0.002) assuming entrance position relative to the cavity is random(**). This non-random distribution can be explained in two ways. Either honey bees select cavities with bottom entrances, or fungal decay, which probably produces most tree cavities, tends to expand upward from its entry point into a tree." (***)
(*) Eh ? Why not analyse the 49 entrances in 33 nests as before ?
(**) which it isn't - ask any tree surgeon.
(***) which is exactly the case. ALL cavities created by wet rot due to rain-water ingress will develop openings towards the bottom, as wood rot develops much faster at the upper surface of the cavity where conditions are damp, but not flooded as tends to occur at the bottom of the cavity.
You might find the following of some relevance to this topic:
"This dampness which causes what may be called a rot among the bees is one of the worst enemies with which the Apiarian in a cold climate, has to contend, as it weakens or destroys many of his best colonies. No extreme of cold ever experienced in latitudes where bees flourish, can destroy a strong colony well supplied with honey, except indirectly, by confining them to empty combs. They will survive our coldest winters, in thin hives raised on blocks to give a freer admission of air, or even in suspended hives, without any bottom-board at all. Indeed, in cold weather, a very free admission of air is necessary in such hives, to prevent the otherwise ruinous effects of frozen moisture; and hence the common remark that bees require as much or more air in winter than in summer." Hive and the Honey Bee, Langstroth, 1853, p.117
LJ