Horsetail Reed has vertical jointed reed-like stalks of medium to dark green. The hollow stems are up to 3 feet in height. The stems are not branched. The stems themselves have conspicuous ridges, which are impregnated with silica. This makes the ridges feel rough and harsh.

The stems are generally deciduous in cold climates, and remain during winter in warmer climates. It forms dense spreading colonies, in full to partial sun.

Due to its high silica content and waxy exterior, chemical control can be difficult requiring multiple applications.