Bob asks why our old-timer used screened bottoms.

First, he used 8-mesh when he could find it.  When he couldn't find it he used window screen.

He started using screened bottoms after bringing a load back from Florida in the late 40's and having large losses due to overheating.  In those days I guess that today's nets were not available, or were hard to get.  So, he put them on screened bottoms hoping to improve ventilation...which it did.  For the first few years he left them on all summer and then changed to solid wood for the winter.  (He spent most of the winter here, and only went to Florida in February for early build up and splits.)

Inevitably, the fall came when he got too busy and an early snowfall caught him with the screens still on hundreds of his hives.  He was surprised in the spring when those with screens did as well as those with solid wood.  From then on, he left the screens on all year.

These are full screens.  Of interest, the bees do not completely propolize them.  Many have almost no propolis, and the worst only propolize the edges and leave the center open.

Lloyd
Lloyd Spear, Owner of Ross Rounds, Inc.
Manufacturer of round comb honey equipment and Sundance pollen traps