FIELD ID CHARACTERISTICS:
This grass is distinguished by its huge, silvery-tan plume spikes and untwisted bristles extending from seeds. Stems below the inflorescence are hairy. Difficult to identify before seedheads appear in fall, though plant in general is large and leaves are long.
Synonym(s): Erianthus giganteus, Erianthus laxus, Erianthus saccharoides
Description: Very tall, robust, perennial grass, with large spike inflorescence on stem reaching high above leaves; flowering stems 3 to 4 m tall.
Leaves: Long blade leaves, 15 to 40 cm long and 2.5 cm wide, rough to the touch when rubbed from tip to base, and along edges. Stem leaf bases and young stem nodes have long, white hairs ("bearded").
Flowers/Fruit: Spikelets on the large inflorescences separate when first appearing, then aging to a fluffy silvery-tan or purplish plume (when dry). Plume may be 35 cm long and 7 cm wide. Long bristles extending from mature seeds are untwisted. Flowering and fruiting late August through October.
Habit and Range: Fresh and brackish marshes, ditches, edges of lakes and swamps. Chiefly lower Piedmont and Coastal Plain; occasional in Mountains.
COMMON CONFUSIONS:
Immature inflorescences of Saccharum giganteum (sugarcane plumegrass) are similar to Phragmites australis (common reed), which does not have fluffy plumes. P. australis has long arching inflorescence branches and is not as compact as Saccharum giganteum. Saccharum giganteum is also similar to Erianthus coarctatus (compressed plumegrass), which is found in the same types of habitats (common in the Coastal Plain mainly), but it has a smooth stem below the inflorescence. Also compare Saccharum giganteum to the less common Zizania aquatica (annual wild-rice), which has a similar but more spreading seedhead.
Click here to view Phragmites australis.
Link to side-by-side comparisons page
