Scientific Name
Phragmites australis (Cav.) Trin. ex Steud. (Synonyms: Phragmites communis)
Common Name(s)
Common reed, giant reed, phragmites
Tribe / Family Name
Arundineae
Flowering Period
July to September
Symbol
PHAU7
Description
Common reed is an introduced warm-season perennial that is rhizomatous or stoloniferous; it reproduces from seeds, rhizomes, and stolons. Culms range from 100–400 cm in height. Its inflorescence is an open, plumose panicle 15–35 cm long and up to 20 cm wide with ascending branches and several-dense spikelets, usually purplish when young, and stramineous when mature. Spikelets are 10–15 mm long, 3- to 10-flowered, and unawned. Ligules are a fringe of hairs and <1 mm long.
General Info
This vigorous reed-like plant can be found in wet or muddy ground in saline or freshwater marshes, edges of ponds, lakes, river floodplains, sloughs, foothills, and plains.
Similar Species
Common reed’s appearance is similar to American common reed, the native form of this grass. Typically, there are several vegetative characteristics that can help separate these two species from each other, but only the most diagnostic features will be listed in this book. Please consult other sources when trying to distinguish these types of plants. American common reed: ligules >1 mm long, lower glumes 3–6.5 mm long, upper glumes 5.5–11 mm long, loose leaf sheaths (drop off easily), and generally grow in mixed communities with low to high stem density. Common reed: ligules <1 mm long, lower glumes 2.5–5 mm long, upper glume length 4.5–7.5 mm long, tight leaf sheaths (remain on dead stems), and often grow as a monoculture with a high stem density. Also, there is a ‘Gulf Coast lineage’, also known as subtropical common reed, but its distribution is restricted to the southern most states in the United States, as well as northern Mexico, Central America and South America.
Picture of growth habit.
Close-up picture of open-panicle inflorescence (immature growth stage).
Close-up picture of open-panicle inflorescence (mature growth stage).
Close-up picture of spikelet.
Close-up picture of hairy ligule.
Illustration of common reed. USDA-NRCS PLANTS Database / Hitchcock, A.S. (rev. A. Chase). 1950. <i>Manual of the grasses of the United States</i>. USDA Miscellaneous Publication No. 200. Washington, DC.