"Timothy" wrote in message
s.com...

I would suggest that you use a 4X4 or even a 6X6 piece of NoN-treated
wood. Pine, fir or cedar is best. I would also suggest that you drill
serveral holes of different sizes from 9/32 to 5/16 in size about a 1/2
inch to 3/4 inch apart. The term "mason bee" is a catch all for a range of
solitary bees that live around you. These bees will be of differing sizes
and with the varied hole sizes you'll get a broader collection of bees.
The different bees will emerge at different times and will give you a bit
of a longer season to enjoy your bees. With a few blocks, you'll soon see
which hole sizes are best for your area and that will direct you in the
furture when making new blocks. I was told to scorch the block's front to
make the block more atractive to the bees. This may or maynot be true.
Both my blocks filled up. Here's a good link:
http://www.pollinatorparadise.com/So...s/SOLITARY.HTM

I found an excellent example on this web page:
http://www.birdcrossstitch.com/garden/Journal.html