Acorus americanus Sweetflag

General

Formerly classified as Acorus calsmus. Sweetflag is an obligate wetland plant found on shore edges and shallow water, with tall, lance-like blades and a sweet, spicy citrus fragrance when crushed. Sweetflag, despite the appetizing name and fragrance, should not be consumed by humans.

Plant Description

Sweetflag grows in clusters on shore edges, with the lance-like leaves growing to four feet tall. Flowers are green and brown rounded spathes, each a few inches long, which grow from the middle of the plant. The plant spreads and grows via rhizomes once established.

Height (ft)
4

Soil moisture
Moist, High

Soil types
Fine to Medium texture, muddy soils

Wetland indicator
OBL

Shade tolerance
Intolerant, Full Sun

Bloom color
Green, Yellow

Bloom period
Summer

Drought tolerance
None

Salinity tolerance
None

 

Distribution

Northeastern United States, from Maine west to Minnesota and South Dakota, and south to New York, with isolated populations in Idaho.

Additional information

“Acorus Americanus.” Wikipedia, Wikimedia Foundation, 16 Aug. 2021. LINK

Brown, Lauren. Grasses: An Identification Guide. Houghton Mifflin Company, New York City, 1979. LINK

Fassett, Norman C. A Manual of Aquatic Plants, First Edition. McGraw-Hill Book Company, Inc., New York and London, 1940. LINK

Garbisch, Edgar W., and McIninch, Suzanne M. Propagation of Wetland Plants: Herbaceous Plants, Shrubs and Trees. Environmental Concern, Inc. 2003. LINK

Harris, James G., and Harris, Melinda Woolf. Plant Identification Terminology: An Illustrated Glossary, Second Edition. Spring Lake Publishing, Spring Lake, Utah. 2011. LINK

Hitchcock, A.S., and Chase, Agnes. Manual of the Grasses of the United States, Second Edition, Volume I. Dover Publications, Inc., New York, 1971. LINK

Kartesz, J.T., The Biota of North America Program (BONAP). 2015. North American Plant Atlas. (http://bonap.net/napa). Chapel Hill, N.C. [maps generated from Kartesz, J.T. 2015. Floristic Synthesis of North America, Version 1.0. Biota of North America Program (BONAP). (in press) LINK

McKenny, Margaret and Peterson, Roger Tory. A Field Guide to Wildflowers of Northeastern and North-central North America. Houghton Mifflin Company, 1968. LINK

Newcomb, Lawrence. Newcomb's Wildflower Guide. Laurence Newcomb, Mexico. 1977. LINK

USDA, NRCS. 2021. PLANTS Database (https://plants.sc.egov.usda.gov/, 08/20/2021). National Plant Data Team, Greensboro, NC 27401-4901 USA. LINK