The Plants of Michigan / Simple Keys for the Identification of the Native Seed Plants of the State

by Henry A. Gleason

1a. Leaves compound [— 2.]
1b. Leaves simple [— 3.]
2a. Leaflets 3, spathe pale green or purple (3-6 dm. high; spring)	Indian Turnip, Arisaema triphyllum.
2b. Leaflets 7-11; spathe green; spadix long and slender (3-8 dm. high; late spring)	Dragon Root, Arisaema dracontium.
3a. Leaves linear, sword-shape; spathe none (5-15 dm. high; early summer)	Sweet Flag, Acorus calamus.
3b. Leaves broader than linear; spathe present [— 4.]
4a. Flower clusters partly underground, appearing in earliest spring	Skunk Cabbage, Symplocarpus foetidus.
4b. Flower clusters peduncled, in early summer [— 5.]
5a. Leaves broadly ovate-cordate; spathe white	Water Arum, Calla palustris.
5b. Leaves more or less sagittate; spathe green	Arrow Arum, Peltandra virginica.

LEMNACEAE, the Duckweed Family

Minute leafless plants floating on quiet water; flowers exceedingly small and seldom seen.

1a. Plant thick, ovoid, less than 2 mm. long; roots none. Two species are reported from Michigan	Wolffia spp.
1b. Plant flattened, with short roots [— 2.]
2a. Roots several from each rounded plant	Duckweed, Spirodela polyrhiza.
2b. Root single from each rounded plant	Duckweed, Lemna spp.
Three species are reported from Michigan, of which the commonest is Lemna minor.

ERIOCAULACEAE, the Pipewort Family

Bog or marsh herbs, with small flowers in heads terminating long slender scapes.

One species in Michigan; leaves linear and basal; flower-stalk 5-15 cm. high; flower-heads whitish or lead-color

Pipewort, Eriocaulon articulatum.

XYRIDACEAE, the Yellow-eyed Grass Famil

Small herbs with basal leaves and erect flower-stalks bearing a head of perfect yellow flowers, in summer.

1a. Base of plant bulbous-thickened (3-6 dm. high)	Yellow-eyed Grass, Xyris flexuosa.
1b. Base of plant not bulbous-thickened (1-3 dm. high)	Yellow-eyed Grass, Xyris montana.