Scientific Note: Arundinaria gigantea and Arundinaria macrosperma, the Correct Names Respectively for the Switch Cane and the Giant Cane

Published:

June 2009

Author

Daniel B. Ward

Additional Authors

Thomas Walter in 1788 described and named two species now assigned to Arundinaria. His two names, Arundo gigantea and Arundo tecta, are now believed to represent not only synonyms but developmental stages of the same taxon. If Arundinaria in the southeastern United States is interpreted to consist of two species, the smaller plant, the Switch Cane, may correctly be known as A. gigantea (Walt.) Muhl. The second, larger plant, the Giant Cane, then becomes A. macrosperma Michx. To provide greater stability to these names, an epitype has been selected for each.

Arundinaria (Poaceae/Gramineae) is a genus of very large grasses, the only widespread true bamboos in North America. In the southeastern United States two taxa are usually recognized, perhaps more readily addressed by their common names than by their uncertain scientific designations. Switch Cane is found commonly on moist soils along the Atlantic seaboard, from eastern Virginia to central peninsular Florida and west along the Gulf of Mexico to southern Mississippi (Gilly 1943, Triplett et al. 2006). Giant Cane forms dense stands or ‘‘canebreaks’’ on bottomlands from the western Carolinas throughout the lower Mississippi River valley and south from northern Florida to eastern Texas. The two taxa seem securely separated by the presence in the rhizomes of Switch Cane of a ring of conspicuous peripheral air canals or lacunae, a character absent in Giant Cane (McClure 1963, Triplett et al. 2006). The spikelets carry additional diagnostic characters—in shape, color, and pubescence of the glumes (Gilly 1943)—though the usefulness of spikelet characters is limited by the infrequency (often spanning decades) with which the plants flower. Vegetative characters, including pubescence and length of the sheath and blade, have also been noted (Hitchcock 1951, Triplett et al. 2006), though they are less obvious and perhaps intergrading.

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