This is a commercial site, but they do a lot of education work and have lots of good info on their site:<p><a href="http:&#x2F;&#x2F;crownbees.com&#x2F;learn-mason-bees" rel="nofollow">http:&#x2F;&#x2F;crownbees.com&#x2F;learn-mason-bees</a><p>I bought two starter tubes of blue orchard mason bees four years ago. Last year, I collected 100 filled tubes (natural reeds) of bees. Crown Bees recommends not using holes drilled in lumber because they&#x27;re not very reusable and can spread disease (can&#x27;t be cleaned). The bees seem to like natural reeds the best. I store my bees in their tubes in the fridge in a humidified box during the winter months, and harvest the tubes in April. I split open the tubes and collect and inspect the cocoons. Each tube can have 8-10 cocoons, although some fail completely. The population can grow very quickly when you care for them this way.