Teasel is an invasive plant where I live, and the orchard mason bee is a
native, so I don't feel guilty about uprooting teasel to make homes for
mason bees. If you gather them during the growing season, gather the biggest teasel plants you can find. It will be easier to drill out because the skinnier ones aren't wide
enough. Search for teasel on google images and you will probably recognize it, that's how I did. With the fresh growing teasels, cut them into sizes about 6". THe teasel tubes are internally blocked off on one side, which is perfect. You can literally jam a long pencil down it for 6" long because like he said on the
video the pencil is 5/16" wide and make them quickly on a freshly growing one. If you use dormant season teasels, you'll have to use a drill. The drill bit will probably have to be a special one, because most drill bits are about 4". You won't get the right ratio of male to female with like 2-3" of tube. A 12" drill bit is what I got, about $10, well worth it. A PVC pipe with an angled cut to make a roof on the top on each side works great to house the reeds. Put a dab of whiteout on the drill bit to know when you get near 6". You can switch the sides of the tube you use to keep the roof on top when you're cutting, say a 10' PVC tube into individual sections for houses. Each house for
bees could be about 13-14" long on the long sides if you want it pointing both ways, so you have a few inches for a roof on each side. Even number of tubes. Hanging them toward the east for morning sun works well if you're only going one direction. You can put them in a tree so during the summer the leaves will stop them from getting too hot. Metal gets too hot if in the open.
Cardboard disintegrates in the rain. PVC/plastic seems best. I recycled mine. SOmetimes the
bees will wait a year to use it, so I prefer to gradually increase my mason bee population. The winter is a good time to prepare the reeds because there's less to do in the garden and you need to be ready when February/March comes with the blooms and the bees waking up. I also did notice the sunchoke/Jerusalem artichoke and I'm going to try that this winter too. Ask away if you have questions or share your ideas so we can learn more.
John S
PDX OR