puzzled by Screened bottom board design.

[mrspock]

A neighbor recently ordered an SBB from a regional supplier. The specific design is like nothing I've seen before. I mailed the supplier and asked, and received a stock answer about varroa control.

I've attached a picture. The part of the left is a fairly basic Bottom board, but is about 2" deep. The middle component is a piece of 1/8" board. The piece on the right is a 1" deep frame with a screen on it. As best I can figure, this is a cold-weather SBB to allow screened space for mite-drop without actually opening up the bottom.

According to the supplier, the thin board in the middle is to place a stickyboard on. I don't see why this is necessary, as it seems the sticky board could be placed right under the screened frame. Moreso, when a hive body is placed above the SBB, there is little space to actually lift the screened frame in order to slide anything underneath of it.

Altogether, this seems like an insane design, but given that beekeepers are constantly improving/innovating equipment, I have trouble accepting that this is a mistake, and am wondering if there's a design brilliance here that I simply don't get.

Can anyone offer any insight?

[fish_stix]

Ever go into a fishing tackle store and see all the thousands of pretty lures they sell? Fishermen could get by with 3 or 4 colors that resemble the bait that fish actually eat. But those pretty colors sell like hotcakes! Works the same with beekeeping equipment.

[valleyman]

The best I can tell from your picture is what I bought about 5 years to be used for catching falling mites on sticky boards. They were never intended for ventilation. Thus the new SBB that is open on the bottom directly to the frames in the bottom chamber. It is designed for mite counts with the plastic cardboard insert or can be closed off with the insert leaving what ventilation you want. I leave mine wide open year around, but in Canada you might want to close it part way during the severist cold weather.

[doc25]

From what I've read all you need is for mites to drop about 1" to keep them from getting back into the hives. The thin board could also have vaseline applied to it so the mites could stick to it. From personal experience I would make sure that the board is closed off in the bottom to overwinter. Do not open it up too early in spring either, I would leave it blocked off until it gets pretty hot. I would think that the bottom board has a groove or block arrangement to allow the thin piece of ply to be removed when wanted.

I have made some of my own and use a groove directly below the screen in which I insert a piece of black coroplast that I can pull out if I wish.

[spunky]

Yea, looks like he/she /they used the same cuts for and inner cover, alot of designs for IPM BB's

[KiwiMana]

The bottom of that board would be a great spot for wax moths to breed as well, I wouldn't recommend using that one. Unless its at a site you visit often and clean out the lower tray.

I would think mites would be able to crawl back up to the hive with this one as well.

See ya...Gary
http://kiwimana.co.nz

[Charlie B]

Kinda defeats the purpose of a SBB.