This photo was taken by the Student Plant ID team. It shows many horsetails sprouting and a few sedges filling the streambed (Jan term 2011).
The sprouting horsetails grow rapidly in early Spring. (Photo by S. Bachofer)
The horsetails have an extensive root structures. The actual species is possibly Equisetum giganteum since in the middle of summer these plants reach a height of nearly 2 meters.
This photo was taken in June 2011 when the horsetails are approaching their maximum height. The seasonal wetland was still rather damp and mid-summer rainstorms had occurred a few days before this visit. (Photo by S.Bachofer)