Another widely used piece of beekeeping technology that is deceivingly simple is the two-sided bottom board. The bottom board is exactly what it sounds like. It is the bottom of the bee hive. The ground floor of “Honey Bee Heights” as it were (Think of a tall stack of hive boxes as similar to a tall building and you’ll catch my corny comparison).
Most bottom boards are made of wood. Sometimes one solid piece, more often a few smaller boards attached together. Another type of bottom board is a “screened” bottom board like the one pictured below. It is a wood “frame” with most of the space being a metal screen that the bees can walk on but debris can fall through. Not only debris falls through the screen, pests that have been booted out can drop down through the screen as well. Parasites like Varroa mites in particular. Often beekeepers will place a plastic sheet below the screen covered with vegetable or something else sticky to monitor the number of Varroa that fall through the screen and help determine if there is a need to take some type of action to reduce or eliminate that pest population.
When it comes to the wood, just about any wood will do. Many beekeepers like to use cedar as it has certain natural pesticidal qualities that does not affect the bees themselves. One type of wood that is not used by and large in bottom boards is plywood and similar sheet wood. The reason for that is that in the heat of summer, the glues in the plywood begin to vaporize and rise up into the hive, killing the bees as it does.
Perhaps the most common bottom board sold to beekeepers is the two-sided bottom board. On one side of the board, the edging on which the hive boxes sit is 3/4 inch. Thus when the hive box sits on top of the edging, it leaves a 3/4 inch opening between the bottom side front of the hive box and the bottom board.
Some beekeepers find that they prefer the 3/4 inch side because they want to increase ventilation through the hive and to give the increased population of bees moving in and out of the hive in the warmer months more traffic space. Many other pieces of beekeeping equipment are made to accommodate the 3/4 inch side such as entrance guards and feeders.
On the other side of the two-sided bottom board is a smaller ledge which provides a 3/8 inch entrance instead. There are some beekeepers (such as myself) who feel that the 3/8 inch entrance provides more than adequate ventilation and traffic space and at the same time, improves the bees ability to defend their hive with a smaller area to guard. Combine this with an upper entrance and there is more than enough ventilation. The photo below shows the 3/8 inch side facing up and the 3/4 inch side facing down.
Every hive has a floor or bottom. In trees and other cavities such as walls, etc… you as a beekeeper cannot access it with cutting open the tree or wall or whatever. With a component hive system like the Langstroth or the Warre or even many Horizontal Top Bar Hives built a certain way, a beekeeper has direct access to the bottom or floor at any time. Whether they are looking for Varroa mite counts or how many bees might have died and fallen to the bottom, getting right to the bottom of things, as it were, isn’t a difficult task.