We had more people join our team on Monday night: welcome to Andrew, Kristine, Charity and David. (Did I get the names right? If not, someone leave me a comment and I'll fix them.) It was a general search-and-destroy mission, fanning out from "home base" under the cottonwood trees. Our main target was garlic mustard, which lurks everywhere, but we also pulled up or cut off some young Manitoba maples:

This tree is native to Canada but not to our area; it belongs farther west, as you've figured out from the name. The wood is weak and susceptible to breakage (although those roots are pretty strong!) and because this maple grows and reproduces quickly, it would crowd out our desired species if left unchecked.

Another target was the Canada thistle. I felt some pangs at destroying this lovely symbol of my Scottish heritage. Oh well, I'm not that Scottish, so I hardened my heart and snipped off the tops ...

... which were bagged to prevent the spread of seeds. The rest of the plant we just cut and left on the ground. These thistles will also grow from buds on their root system, but if we can keep the tops cut off the plants should eventually starve. Here's a slaughtered thistle:

The fruits of our labours: