Scientific Name
Arundo donax L.
Common Name(s)
Giant reed
Tribe / Family Name
Arundineae
Flowering Period
May to June
Symbol
ARDO4
Description
Giant reed is an introduced cool-season grass that reproduces vegetatively by rhizomes and stem nodes. Culms 2-10 m in height, 1-4 cm thick, and nearly woody. Inflorescences large plume-like panicles 30-60 cm long and up to 30 cm wide. Spikelets 10–15 mm long, 3- to 7-flowered, and noticeably hairy. Ligules short (up to 1 mm long), membranous, and lined with short hairs along the margins. Blades 30-100 cm long, up to 6 cm wide, flat with scabrous margins, and evenly spaced along the stems.
General Info
Giant reed can be found along roadsides, ditches, culverts, wetlands, and riparian habitats. This bamboo-like grass can grow in dense patches, causing displacement of native riparian flora, such as willows. Uses include musical instruments, scaffolding, walking sticks, and fishing pools.
Similar Species
Giant reed can look similar to reed (Phragmites spp.) plants. To differentiate the two, compare their heights. Giant reed can be up to 10 m in height, and reed plants can be up to 4 m in height. Also, giant reed has thicker rhizomes, wider culms, and broader leaves than reed plants.
Picture of growth habit. Photo by Justin J. Trujillo.
Close-up image of panicle inflorescence. Photo by Justin J. Trujillo.
Close-up image of spikelets and florets. Photo by Justin J. Trujillo.
Close-up image of spikelet. Photo by Justin J. Trujillo.
Close-up image of membranous ligule. Note the small hairs along the margin. Photo by Justin J. Trujillo.
Illustration of giant reed. Hitchcock, A.S. (rev. A. Chase). 1/1/1950.
Distribution map of giant reed. USDA PLANTS Database, 2022.