Typha leaves are alternate and mostly basal on a simple, joint-less stem that bears the flowering spikes. The plants are monoecious, with unisexual flowers that develop in dense racemes. The numerous male flowers form a narrow spike at the top of the vertical stem.
Each male (staminate) flower is reduced to a pair of stamens and hairs, and withers once the pollen is shed. Large numbers of tiny female flowers form a dense, sausage-shaped spike on the stem below the male spike. In larger species this can be up to 12 in (30 centimeters) long and 0.39 to 1.57 in (1 to 4 centimeters) thick. The seeds are minute, 0.2 millimeters (0.0079 in) long, and attached to fine hairs. When ripe, the heads disintegrate into a cottony fluff from which the seeds disperse by wind.