- Group 1Lycophytes, Monilophytes
- Group 2Gymnosperms
- Group 3Monocots
- Group 4Woody angiosperms with opposite or whorled leaves
- Group 5Woody angiosperms with alternate leaves
- Group 6Herbaceous angiosperms with inferior ovaries
- Group 7Herbaceous angiosperms with superior ovaries and zygomorphic flowers
- Group 8Herbaceous angiosperms with superior ovaries, actinomorphic flowers, and 2 or more distinct carpels
- Group 9Herbaceous angiosperms with superior ovaries, actinomorphic flowers, connate petals, and a solitary carpel or 2 or more connate carpels
- Group 10Herbaceous angiosperms with superior ovaries, actinomorphic flowers, distinct petals or the petals lacking, and 2 or more connate carpels
Acorus was traditionally placed in the Araceae. This erroneous placement of the genus was partly due to incorrect interpretation of the distal portion of the sympodial leaf—a structure that had been considered to be a spathe. Two species are now recognized to occur in our area. Acorus calamus is a sterile triploid that has been introduced from Europe. Acorus americanus is a fertile diploid native to North America. References: Haines (2000a), Thompson (2000a).
1a. Secondary veins of dried leaf blades up to ca. 0.5 times the width of the midvein (i.e., leaves with 1 prominent midvein and numerous finer, secondary veins); fruits not produced; sympodial leaf often as tall as or shorter than the vegetative leaves; vegetative leaves (5–) 10–20 mm wide, often crisped or undulate; flowers 3–4 mm long
1b. One or more of the secondary veins of dried leaf blades ca. 0.75–1 times as wide as the midvein (i.e., leaves with 2–6 prominent veins as well as numerous finer, secondary veins); fruit produced, an obpyramidal berry; sympodial leaf usually as tall as or taller than vegetative leaves; vegetative leaves 3–10 (–12) mm wide, not crisped, entire; flowers 2–3 mm long
Show photos of: Each photo represents one species in this genus.