Interesting comments. I have a couple of commercially made screened bottom boards that I?ve been using for years. One is in a poly hive and the other is a galvanised steel base. I also have about 5 bottom boards that I made which use a series of slots in the base for ventilation. The Bluebees board is what I?m talking about here. It has a series of semi circular sections or ridges that the bees walk on. Beetles tend to be chased out through the slots and all debris falls through the slots. It is one bottom board that never needs cleaning. I have been reading that screened bottom boards have a small impact on varroa numbers and are only partially effective. Is that what you guys are finding? The information that I?ve been getting is basically saying that it is only one minor component of a management system to help control varroa. If the information I?m getting is wrong, please let me know. I want to do as much as I can to prepare for the invasion that will hit. As far as the cost is concerned, that is a real consideration. I have been using an aluminium mesh for years in some of the beekeeping projects that I?ve made and it may end up as a cheaper option. I used some of this screen recently on the pollen trap that I made. Bees can?t get through it but small hive beetle can. The issue I had with the aluminium screen was the fact that I couldn?t buy it in the widths that would cover a bottom board. This meant that joins were required which became problematic. I found out a couple of days ago that it is now available in sizes that will suit my needs. Although much softer than stainless, it is very easy to cut with hand tools and bends readily. If I buy a roll, a piece for a bottom board would cost less than $4. I?ve read a lot about SBB?s over the years and I can see good arguments both for and against. The climate that you live in could tend to influence any bias one way or another. In my own situation, I leave the vented and screened boards open all year round. Observations on my part have only been anecdotal and not recorded but here goes. The hives have always been strong and healthy. I have noticed no difference in the strength of hives with or without SBB?s. The only exception to that is the poly hive that I?ve had for about 10 years. It is always a bit larger and stronger on average than the rest of my hives. Condensation is always less in these hives. Small hive beetle numbers appear to be consistent with beetle numbers in all other hives. The numbers appeared to be a bit lower in the hives with Bluebees bottom boards. Honey production appears to be similar to hives with a solid bottom. Again, the one exception is the poly hive that tends to end up with a higher honey yield than other hives. (Not always but it is always near the top producer). So in summary, in my situation in a temperate climate, a screened bottom board has no disadvantages but the question still remains. Will it have some impact on varroa? If the answer is a definite no, then there is no reason to change. If there is only a minor impact on varroa, a change is definitely an option. I have been designing a SBB that should be simple to make but I would like more feedback before I get started.
