mason bee holes: how deep?

[ThisBud4U]

Hello,
I'm trying to create my first "homes" for mason bees, and I'm wondering how deep the holes need to be. I've bought some untreated 4X5 inch pine from Home Depot, and I could either drill into the 5" side or the 4" side. Somewhere I read that the holes should be 5/16" x 5" deep, but that would necessitate some fancy drilling, since my drillbit only goes 4" deep. Does anyone know if 4" holes would be sufficient? Obvious complete newbie here, any help greatly appreciated.
ThisBud4U

[DavesBees]

Check the post below by Omie “ my first year for mason bees”. To answer your question, I would say drill the 5 inches clean through with a longer 3/8 inch drill bit and put paper tubes in the holes. Then put a back on the block. If you use your bit and wish to make a throw away block it will work, however the bees will provision less females than in a deeper hole. The block will become fouled after a few years and you will have to redo them. I started this way myself but with a longer 5/16 bit.

[ThisBud4U]

Thanks, Dave.
I've got four pieces of wood now with 92 holes per piece, 5/16" diameters. I'll need a bunch of those paper inserts before long. Which brings me to another question:

For those inserts, is paper the best material, or might a plastic insert be more durable? Or would the bees prefer something more "natural" like paper? Is there any information on whether the bees have any preference at all?

[Omie]

Bud,
Bees prefer paper over plastic liners by far. Also plastic doesn't breathe and encourages fungus.
Buy a roll of kitchen parchment paper for use in baking (fancy kitchen stores and large supermarket have it in the baking dept.) It's easy to cut and roll.
Watch Dave's video and read his site on it- very informative.

[DavesBees]

ThisBud4u

The holes you have now are too small for paper tubes, you will get a few small mason bees but not as many as with the 3/8 holes. Your blocks will work fine at 5/16 without paper tubes. Remember my 3/8 tubes with the 3 wraps of paper are close to 5/16 available to the bees. My block with 3/8 holes is clean full and I had to put up extras. The paper I use is parchment paper from the grocery store. I cut them into dollar bill size pieces, roll them on a pencil and stuff them in the holes. There is a thread below with the following link you should check out. Watch the video in the first post and see if it helps you out.

http://www.beesource.com/forums/showthread.php?t=237673

I’m pretty sure it is too late for you to put your blocks up this year. I’m in Ohio and the mason bees are a spring event lying dormant until the following spring. The plastic tubes or straws may cause problems with condensation; best to go naked or use paper tubes.

[DavesBees]

What Omie said,
While goofing around I had not seen her post. Thanks Omie.