Common Reed

Common Reed
Common Reed. Phragmites australis or P. communis.
Poaceae, the grass family.

Plant: A tall grass with dramatic purple-brown plumes, 5'-15' high, growing in dense stands in wetland areas. Perennial.
Flowers: Purplish brown, in multiply branching, plume-like terminal cluster to 12" long, on thick stems. The flowers themselves are tiny with the threefold symmetry found in all grasses. Later in the fall, the plumes turn downy and silvery.
Leaves: Linear, blue-green, to 20" long, emerging at nodes along, and sheathing the flowering stem. Edges rough, with minute teeth.
Fruit: Seeds contained in terminal plumes, but rarely produced. The plant spreads through underground rhizomes.
Blooming: August-September.
Habitat: Marshes, wetlands.

Comments: This spectacular grass forms dense stands in wetland areas, sometimes crowding out all other plants. It is native to both Eurasia and North America. It rarely produces viable seed, but spreads through rhizomes that grow underground, and sometimes run above ground thirty feet or more. There has been a recent increase in invasive propagation of this reed in wetland areas. At one point it was believed that the species was an aggressive import, but it is now clear that the species predates the European colonization of North America. It is possible that a more aggressive European variety is responsible for the recent proliferation. In some areas human changes to the hydrology may also play a role. The species is sometimes called giant reed, but that name is better reserved for another plant, Arundo donax, which is much larger, and invasive in more southern coastal areas of the US, but is not found in our area.

Where to find it: Large stands of this reed grow in and around the drainage ponds on the northwest side of the park, and along the slough that enters the west end of the pond.