This is in reference to a thread started by Pasquale - or, more specifically, to a reply by vitog about mason bees nesting in his japanese knotweed: http://www.botanicalgarden.ubc.ca/forums/showthread.php?t=47547 I'm curious what you do to the knotweed, if anything, to make it more inviting to passing mason bees? Besides releasing'em, growing attractive plants, & then crossing your fingers, how do you convince passing bees to not only pollinate your garden but to move into your knotweed too? Or are those 2 automatically linked? I have a TON of miner bees living in my front yard (certainly >>100) esp in an old rock wall & now in the rich mulchy soil of my PNW native garden. It's always cool when they start to emerge en mass, atho it's also kinda disturbing to dig them up while I'm gardening. I've always thought I was waking 'new borns' prematurely & dooming them to an early death. But I just found out that ground bees continue to sleep & hibernate underground, even as adults (phew!). Anyway, I have no idea how the miners 1st showed up (decades ago), and I don't even know if I already have mason bees nesting on my property!! But, assuming I don't, how do I get them to find & nest in the knotweed? Thx.
Dried knotweed stems from last year are used as tubes in the same way that cardboard tubes are used in Mason Bee houses. I select stems that are straight and the right inside diameter (3/8" is ideal). The stems are segmented, and the ideal segment length is about 6", but the length is not critical. Obviously, segments longer than 6" can be shortened. I keep the segment partition at the back of each tube to close it off and provide strength. I've found that a fine-toothed hacksaw works very well for cutting the knotweed stems into individual segments. After you've made enough knotweed tubes, you just need to enclose them in one or more houses. Almost anything that provides protection from the weather will work. I have two really old houses that I bought from Bee-Diverse when I first started keeping Mason Bees. These are made from painted plastic Coke bottles and will hold about 25-30 knotweed tubes. I just bundle the tubes inside some flexible foam for insulation and shove them into the Coke bottles, which are then mounted about 8 ft high on the posts of my south-facing deck. I've also made several bee-houses from rigid styrofoam sheet insulation, 1" thick, by cutting it into pieces and gluing them into a box shape with an open front. I fill the box with tubes and wrap flexible roofing tar-paper around the whole thing, making sure that there is a substantial overhang to keep rain off the tube entrances. The Mason bees really like the knotweed tubes, and almost anything can be used to house them. It's probably best to have the bee-houses ready by late February or early March.
Excellent! I'd expected you were just drilling holes into each vertical chamber, but this makes far more sense and it sure beats buying a $30 glorified birdhouse or rolling all those little paper tubes by hand. Do you harvest your knotweed early so that the shoots don't get too wide or do you simply lop off the thinner top end? A lot of my shoots are already >1" diametre so maybe I'll have to raid the little ones while I still can. Very cool. Thanks for the tip! I'm excited to set that up for next year!! :)
The best way to start your Mason bees colony,it would be to get hold of some bee cocoons, that way you are assure of some bees activity right the first year. The other way of waiting and see, could take more than one year if they are not around in your area.
Fern2, you don't have to do anything special to harvest the knotweed for making tubes. Just wait until winter when all of the stems have died and dried up. I just go to a nearby area where the knotweed grows rampantly as a weed and collect portions of the stems that are the right size. You can usually make 2 or 3 tubes from each stem; the rest is the wrong diameter.
