Screened bottom board - when should the board be in vs. out?

[bison]

I'm trying SBB's this season and am not sure when I should have the removable sliding board in versus out. Clearly it will ventilate better out, so in the summer I presume it should be out. Likewise in winter probably better to have in to keep the hive warm. Any guidelines to optimize the benefits of SBB's?

thanks -

[chevydmax04]

I live in Wisconsin, I have SBB on I thought all my hives and I do not put the sliding board in ever, even in winter. This year I had only one hive not make it, and that was the one hive that did not have a screened bottom board. My theory was mites and SHB are almost always present, when the bee's knock them down in winter they don't come back when there is a SBB.

[psfred]

I put the sliding board back in during the winter, but that's because we have damp, dreary weather a lot. I'll be taking it out when I see bees fanning on the entrance. I know a lot of people only put them in to check mite drop, but I don't want that much "ventilation" in my hives, I'd rather let the bees control it. I've not had any problems with condensation with the board in, but I did put a top entrance on the candy board I put on this winter, which they have used all winter.

Peter

[BeeGhost]

Bison, im across the bay in Livermore and although ive only been at beekeeping for a year, I dont use the slider boards at all and have not lost a hive to being "over ventilated" at all. Infact, I havnt lost any of my 5 hives yet! <knock on wood>

I wouldnt worry about using them here in the bay area, we dont have weeks on end of below freezing weather like the great white North!!

[Michael Bush]

I leave them in until they are bearding. I leave them out until the first frost.

[Charlie B]

The only time you need them here is for mite count.

[indypartridge]

The only time I put them in is when I'm doing a mite count, otherwise they are out - even during winter.

[timgoodin]

I did a not so scientific experiment this winter. Of twenty five or so hives I put the slide into four and left all the others open. All four of the ones with the board in have larger populations this spring that those without the boards in. Could be our mild winter?

They definately appeared to be more moisture in those hives and lots of trash on the bottom boards on spring cleanup. They appear to have gotten a jump on the other hives in terms of early buildup by perhaps one brood cycle. Most average 7 frames of brood while other single hives around five. If we had a cold winter then I'm not sure they would have had enough ventilation in my area and may have froze out due to moisture problems. The ones left open have done ok just not as fast to brood up and definately dry. I think it all depends on how cold it gets, how much water your honey or syrup has going into winter (late syrup feeding vs capped honey from summer flow) genetics of the bees, age of the queens, etc.

I tend not to put all my eggs into one basket so hopefully something will live through the winter for spring splits. I plan to keep trying different things to see what works best in my area.

Tim

[KQ6AR]

We also only use them for counting mites.

[tefer2]

Mine go in on the first frost, I pull them when the nightime temps are 55 and above. Every year I keep leaving them in longer and longer