Very narrow long upright leaves, marshy areas. Gap between the two parts of the flower stalk.
Similar species: Common Cattail (Typha latifolia) - Leaves wider. Blue Flag Iris (Iris versicolor) - Much smaller, has "real" flowers that are blue. Yellow Iris (Iris pseudacorus) - Leaves are very similar but wider, and has large showy yellow flowers.
Flowers: Summer; Green/Brown; Male flwoers on top, female flowers below, with a gap of 1/2"-1" between them.
Single Narrow-leaved Cattail plant. Note the very narrow leaves.
Narrow-leaved Cattail flowers. The pollen is in the upper part, and spills down onto the lower part where the seeds are formed.
Note the gap between the upper and lower parts. This is in contrast to Common Cattail (Typha latifolia), which has no gap.