Acorus americanus (Raf.) Raf.
American sweet-flag (sweetflag)
Acoraceae (Calamus family)
Introduction to Vascular Plants
American sweet-flag (sweetflag)
Acoraceae (Calamus family)
Introduction to Vascular Plants
Species Information
General:
Perennial aquatic herb from a thick rhizome; stems 20-60 cm tall.
Leaves:
All basal, linear, erect, 40-80 cm long, 0.8-2 cm wide, the midveins offset.
Flowers:
Inflorescence a dense, fleshy, linear, 5- to 10-cm long spike subtended by a leaflike bract, the bract as long as or longer than the flower stem; flowers perfect; perianth of 6, scale-like, yellow or brown sepals.
Fruits:
Broadly pyramidal, hard, dry, gelatinous within.
Notes:
Packer and Ringius (1984) have shown that our fertile diploid species is different than the sterile triploid Eurasian species (A. calamus L.) which is introduced in E North America.
Illustration
If more than one illustration is available for a species (e.g., separate illustrations were provided for two subspecies) then links to the separate images will be provided below. Note that individual subspecies or varietal illustrations are not always available.
Illustration Source: The Illustrated Flora of British Columbia
USDA Species Characteristics
Flower Colour:
Yellow
Blooming Period:
Late Spring
Fruit/Seed characteristics:
Colour: Green
Present from Summer to Fall
Source: The USDA
Ecology
Ecological Framework for Acorus americanus
The table below shows the species-specific information calculated from
original data (BEC database) provided by the BC Ministry of Forests and Range.
(Updated August, 2013)
The table below shows the species-specific information calculated from
original data (BEC database) provided by the BC Ministry of Forests and Range.
(Updated August, 2013)
| Site Information |
Value / Class |
||
|
Avg |
Min |
Max |
|
| Elevation
(metres) |
1525 | 1170 | 1880 |
| Slope
Gradient (%) |
32 | 0 | 65 |
|
Aspect (degrees) |
270 | 270 | 270 |
| Soil
Moisture Regime (SMR) [0 - very xeric; 4 - mesic; 8 - hydric] |
3 | 3 | 4 |
| Modal
Nutrient Regime
Class |
C | ||
| #
of field plots species was recorded in: |
2 | ||
| Modal
BEC Zone Class |
|||
|
All BEC Zones (# of stations/zone) species was recorded in |
|||
|
Source:
Klinkenberg 2013
|
|||
Habitat and Range
Shallow water in the montane zone; rare in S BC east of the Coast-Cascade Mountains; N to AK and NT, E to PQ and NB and S to ME, PA, VA, IL, IA, NE, MT, ID and WA.Status Information
Synonyms
Synonyms and Alternate Names:
Acorus calamus L.
Acorus calamus var. americanus (Raf.) H.D. Wulff.