What closed brood tells you three weeks early
Recording capped brood separately from eggs is the single most useful thing you can do in an inspection. Here is the arithmetic behind why.
A frame of capped brood is a promise. The bees inside it will emerge in roughly twelve days, and they will start foraging about a week after that. Count the capped frames and you know, with less guesswork than any other reading, what the hive’s workforce looks like at the end of the month.
This is why BeehiveMind records open and closed brood as two separate figures rather than one. Eggs and uncapped larvae tell you what the queen is doing right now. Capped brood tells you what the colony will be able to do later. Collapsing them into a single “brood” number throws away the timing, and the timing is the part you can act on.
Reading the pair together
High open brood with low closed brood usually means the queen has only recently come into her stride — a new queen, or one recovering from a dearth. The hive will look thin for another fortnight and then improve on its own.
The reverse — plenty of capped brood and almost no eggs — is the reading worth stopping for. It means laying has dropped off. Sometimes that is seasonal. Sometimes the queen has failed, and you have about two weeks of emerging bees to notice before the population starts falling.
Why the app asks for frames, not cells
Every quantity in BeehiveMind is relative to a whole frame, including the halves you round to. Counting cells is more precise and nobody does it twice. Counting frames is a judgement you can make with a frame in your hands and a phone in your pocket, and it stays consistent across a season — which is what makes the chart worth reading at the end of it.