First up is a species I was not familiar with at all before that summer. It was a beautiful thistle, but highly invasive, native to Europe, Central Asia and North Africa. Every stage of the plant is attractive, but it was pretty much taking over any disturbed soil. It is Nodding Thistle, Carduus nutans. I don't have a picture of the rosette, but it was large and spiked all over, looking quite nifty. Here is the bud developing.
It grew tall, and the flower head was large, a couple inches across. As it matured, the flower would turn to face downward, thus "nodding."
This picture doesn't have the flower in focus, but it does show how prickly the whole plant is. It's about as uncomfortable to touch as our Bull Thistle.
Next up is a plant that was growing on/in most of the ponds. This is White Water Crowfoot, a buttercup, Ranunculus aquatilis. It's native to the western US, but can really clog up ponds. And it prefers slow-moving water, so we made it very happy. When it blooms, the flowers are only about an inch across and stick up out of the water, but the roots and leaves make huge floating mats of vegetation.
Let me say, that I wasn't quite at the beginner stage of plant mania, but it had only been a couple of years earlier that I was challenged to be more professional and learn scientific names. (Maybe I'll tell you about that trip some day.) And, I certainly hadn't been introduced to the idea of major efforts to remove invasives. But I was beginning to be aware of their problems.
Here's a real baddie. You probably know this one, especially if you do trail work. This is one of the primary invasive species on everyone's hit list. It's Multi-flora Rose, Rosa multiflora. It's native to the Far East and was brought here as a garden plant. It forms large dense shrubs that crowd out everything else. Not to mention the thorns.
You might be surprised to learn that teasel is also alien and invasive. You can't tell from this picture, but I remember that it's Cutleaf Teasel, Dipsacus laciniatus. I've featured this plant on the blog a few times because it also grows around here. Anyway, the flower heads are pretty and the seed pods are nice in dried arrangements. Those spiky seed heads have also been used historically to do things such as card wool. But it can form monocultures and crowd out other plants.
While we are on the topic, let me just say that cattail, Typhus sp., is native, but it can also form monocultures and crowd out pretty much everything except muskrats and red-wing blackbirds. There is considerable discussion about how much of it should be allowed to grow and fill in ponds and wetlands. There isn't one right answer. If your wetland is for water treatment, it really doesn't matter. But if you want to create a diverse environment for visual enjoyment and wildlife habitat, you may need to do something to keep the cattails in check.
When I went back to U of M that fall and began working on the constructed wetland project at Matthaei, one of my duties was to try to promote native plants and remove invasives. I got real familiar with the myriad invasives and up-close-and-personal muddy all the time digging and pulling. It was a never-ending job. However, none of that was on my job description here.
In other news: I wrote my Get Off the Couch column and edited.
 | See Inside Duties |
