Iris pseudacorus L. (in English known as “Yellow Iris” and in German as “Sumpf Schwertlilie” or “Wasser Schwertlilie) is today's “Plant of the Day”. The species belongs to the Iridaceae family. It's a monocotyledon; that means it as only one cotyledon after germination. The Monocotyledons are a great sub-group of the angiosperms. The Cyperaceae or the Poaceae (grasses) for example are also monocotyledons.
I. pseudacorus - habitus
I. pseudcacorus is a very large flower (80 – 100 cm) with long, sharp-edged and sword-shaped leaves. They are greyish green and have a striking, strong midrib. They are unifacial; that means, that the entire leaf-blade was made by the ventral side of the leaf-primordium. So, you can finde stomatas all over the leaf-blade, which in fact only consists of a ventral side.
Sometimes, the leaves can be confused with the leaves of Acorus calamus L., which also gives the species its name (“pseudacours” means “Fake Acorus). Anyway, the leaves of A. calamus have some strong “side rips” (see the picture in my last “Article of the Week”).
I. pseudacorus - flower
The cygomorphic flowers are yellow and consists of six equal shaped leaves (Tepals). Such a perianth is also called a perigone. There are also three stamens and three carpels (this threefold of the flower is basically a typical character for many monocotyledons).
I. pesudacorus - flower
The plant is native to Eurasia, but can also be found in North America as Neophyte. As you can maybe imagine through my articles about the field trips to Lake Unterbach and Lake Uemmingen, I. pseudacorus grows at marshes, swamps and wetlands. It prefers wet clay soils, but also tolerates a certain height of water.