THE PLANTS OF MICHIGAN

PINACEAE, the Pine Family

Trees or shrubs, usually evergreen, with needle-like or scale-like leaves; fruit a cone or berry.

1a. Leaves in clusters of 2-5 — 2.
1b. Leaves mostly in clusters of 10 or more, on short lateral wart-like branches, deciduous each autumn Tamarack, Larix laricina.
1c. Leaves not in clusters — 4.
2a. Leaves in clusters of 5 White Pine, Pinus strobus.
2b. Leaves in clusters of 2 or 3 — 3.
3a. Leaves 8-15 cm. long Norway Pine, Pinus resinosa.
3b. Leaves 2-4 cm. long Jack Pine, Pinus banksiana.
4a. Leaves alternate or scattered — 5.
4b. Leaves opposite or whorled — 8.
5a. Leaves four-sided — 6.
5b. Leaves flattened — 7.
6a. Leaves 6-12 mm. long Black Spruce, Picea mariana.
6b. Leaves 15-25 mm. long White Spruce, Picea canadensis.
7a. Leaves short-stalked, 15 mm. long or less Hemlock, Tsuga canadensis.
7b. Leaves sessile, 15-30 mm. long Balsam, Abies balsamea.
8a. Leafy twigs soft and flattened White Cedar, Thuja occidentalis.
8b. Leafy twigs not distinctly flattened — 9.
9a. Leaves opposite — 10.
9b. Leaves in whorls of three — 11.
10a. Erect shrub or tree Red Cedar, Juniperus virginiana.
10b. Prostrate or spreading shrub Creeping Cedar, Juniperus horizontalis.
11a. Erect shrub or small tree Juniper, Juniperus communis.
11b. Spreading or ascending shrub, growing in dense mats Low Juniper, Juniperus communis var. depressa.


TAXACEAE, the Yew Family

Shrubs, with needle-like evergreen leaves; fruit red and berry-like.

One species in Michigan; straggling shrub 1-3 m. high Ground Hemlock, Taxus canadensis.


TYPHACEAE, the Cat-tail Family

Erect plants 1-2 m. high, with linear leaves and terminal spikes of brown flowers, appearing in summer.

1a. Staminate and pistillate portions of the flower-spike contiguous, the latter 2.5 cm. in diameter Common Cat-tail, Typha latifolia.
1b. Staminate and pistillate portions of the spike separated, the latter 2 cm. or less in diameter Narrow-leaved Cat-tail, Typha angustifolia.


SPARGANIACEAE, the Bur-reed Family

Marsh plants with linear leaves and spherical heads of inconspicuous greenish flowers, appearing in summer.

About 5 species occur in Michigan, of which the commonest is Bur-reed, Sparganium eurycarpum.


NAJADACEAE, the Pondweed Family

Aquatic plants with submerged or floating leaves and inconspicuous flowers in summer.

1a. Leaves opposite or whorled — 2.
1b. Leaves alternate — 2c.
2a. Leaves thread-like, 3-8 cm. long Horned Pondweed, Zannichellia palustris.
2b. Leaves linear, toothed, abruptly dilated at the base, 3 cm. long or less (Naiad) — 3.
2c. Leaves entire, not abruptly dilated at base [2]Pondweed, Potamogeton spp.
3a. Leaves about 2 mm. wide, sharply and coarsely toothed Naiad, Naias marina.
3b. Leaves very narrowly linear, with numerous minute teeth Naiad, Naias flexilis.


JUNCAGINACEAE, the Arrow Grass Family

Marsh plants, with linear cylindrical leaves and inconspicuous flowers in spikes or racemes, appearing in early summer.

1a. Leaves all basal; flowers numerous in a spike-like raceme (Arrow Grass) — 2.
1b. Stem-leaves present; flowers in a loose bracted raceme (1-3 dm. high). Scheuchzeria, Scheuchzeria palustris.
2a. Fruit (usually to be seen at the base of the raceme) ovoid or oblong, rounded at the base Arrow Grass, Triglochin maritima.
2b. Fruit linear, narrowed at the base (1-5 dm. high) Arrow Grass, Triglochin palustris.


ALISMACEAE, the Water Plantain Family

Marsh plants, with scape-like stems; flowers with 3 green sepals, 3 white petals, 6 or more stamens, and several separate pistils.

1a. Ovaries in a ring; flowers in panicles (2-8 dm. high, summer) Water Plantain, Alisma Plantago-aquatica.
1b. Ovaries in a head; flowers in racemes or umbels — 2.
2a. Flowers all perfect, in a single umbel of 2-8 flowers; stamens 9 (leaves lanceolate; 15 cm. high or less; summer) Dwarf Water Plantain, Echinodorus tenellus.
2b. Flowers in a raceme of 3-flowered whorls, the lower pistillate, the upper staminate; stamens usually more than nine (1-10 dm. high, summer) (Arrow-head) — 3.
3a. Leaves ovate to linear, not sagittate at base — 4.
3b. Leaves broad or narrow, sagittate at base — 5.
4a. Pistillate (basal) flowers sessile or nearly so (2-8 dm. high, summer) Arrow-head, Sagittaria heterophylla.
4b. Pistillate flowers with obvious pedicels Arrow-head, Sagittaria graminea.
5a. Basal lobes of the leaf conspicuous, triangular, almost or quite as long as the terminal portion — 6.
5b. Basal lobes small, short, linear — 4b.
6a. Beak of the achene very short and erect; rare species Arrow-head, Sagittaria arifolia.
6b. Beak of the achene sharp, incurved at right angles to the body; common species Arrow-head, Sagittaria latifolia.


HYDROCHARITACEAE, the Frog's Bit Family

Submerged aquatics, with inconspicuous flowers in summer.

1a. Leaves all from the base, 2 dm. long or more Eel Grass, Vallisneria spiralis.
1b. Leaves on the stem, 2 cm. long or less Water-weed, Elodea canadensis.


GRAMINEAE, the Grass Family

Grasses, with linear or narrow sheathing leaves, and very small flowers without perianth in the axils of chaffy bracts, appearing in late spring and summer.

Of the large number (over 150) of grasses in Michigan, only the commonest are included here, and the student is referred to the Manuals for a full treatment of them.

Their classification depends chiefly upon the structure and arrangement of the spikelets. These consist typically of a short axis, the rachilla, almost or quite concealed by several chaffy bracts. The two lower bracts are termed glumes, and have no flowers in their axils. Above the glumes are two or more other bracts, the lemmas. In the axil of each lemma, and usually concealed by it, is a smaller bract, the palea, and between the lemma and the palea is a single flower. The number of flowers in a spikelet is therefore normally equal to the number of lemmas. The spikelets are grouped in racemes, spikes, or panicles of various size.

1a. Spikelets one-flowered — 2.
1b. Spikelets with 2 or more flowers — 24.
2a. Spikelets grouped into dense solitary cylindrical spikes — 3.
2b. Spikelets arranged in panicles or in panicled spikes — 8.
3a. Spikelets without awns or bristles, or with short awns not more than 3 mm. long — 4.
3b. Spikelets with awns 2-5 cm. long, terminating the bracts Squirrel-tail, Hordeum jubatum.
3c. Bracts of the spikelet without terminal awns, but the spikelets with one or more long bristles arising from their base — 6.
4a. Spike-like panicle thickened in the middle, more than 1 cm. thick Beach Grass, Ammophila arenaria.
4b. Spike little or not at all thickened in the middle, less than 1 cm. thick — 5.
5a. Lower bracts awned; stem erect, unbranched Timothy, Phleum pratense.
5b. Lower scales unawned; stem branched at the base Floating Foxtail, Alopecurus geniculatus.
6a. Bristles 5 or more at the base of each spikelet Yellow Foxtail, Setaria glauca.
6b. Bristles 1-3 at the base of each spikelet — 7.
7a. Spikelets about 2 mm. long; bristles not much longer, green Green Foxtail, Setaria viridis.
7b. Spikelets about 3 mm. long; bristles much longer, usually purple Millet, Setaria italica.
8a. Spikelets numerous, in long slender symmetrical spikes — 9.
8b. Spikelets in panicles, racemes, or loose spikes — 13.
9a. Spikelets without awns; plants 8 dm. high or less (Crab Grass) — 10.  
9b. Spikelets with awns; plants 12 dm. high or more — 12.
10a. Leaf-sheaths all glabrous. Crab Grass, Digitaria humifusa.
10b. Lower leaf-sheaths hairy — 11.
11a. Axis of the spike flat, with wing-like margins Crab Grass, Digitaria sanguinalis.
11b. Axis of the spike slender, without winged margins Crab Grass, Digitaria filiformis.
12a. Spikes numerous, appressed to the axis of the panicle; tall marsh grass Slough Grass, Spartina michauxiana.
12b. Spikes 2-6, widely divergent; plant of dry ground Blue-joint, Andropogon furcatus.
13a. Spikelets subtended by an ovoid thorny involucre 3-8 mm. wide Sand Bur, Cenchrus carolinianus.
13b. Spikelets without a thorny involucre — 14.
14a. Lower branches of the panicle spreading, bearing staminate flowers, the upper branches erect, with pistillate flowers; aquatic or marsh grass 2-4 m. high Wild Rice, Zizania aquatica.
14b. Panicle uniform throughout — 15.
15a. Spikelets with awns 2 mm. or more long — 16.
15b. Spikelets not awned, or with short inconspicuous awns — 18.
16a. Spikelets in solitary raceme-like spikes; awn about 1 cm. long or more Beard Grass, Andropogon scoparius.
16b. Spikelets in branching clusters; awn less than 1 cm. long — 17.
17a. Leaf-blade 4 mm. wide or narrower; panicle slender Drop-seed, Muhlenbergia schreberi.
17b. Leaf-blade 6 mm. wide or more; panicle stout and coarse Barnyard Grass, Echinochloa crus-galli.
18a. Spikelet plump and compact, its bracts closely folded about each other — 19.
18b. Spikelet very flat, its two bracts closely folded together Cut-grass, Leersia oryzoides.
18c. Spikelet loose and open, somewhat flattened, its 3 bracts ascending or spreading and not closely folded about each other — 20.
19a. Panicle about half as long as the entire plant; leaves copiously hairy Witch Grass, Panicum capillare.
19b. Panicle of smaller size Panic-grasses, various species of Panicum.
20a. Panicle strongly contracted or spike-like; plants of sand-dunes — 4a.
20b. Panicle spreading or slightly contracted; axis of the spikelet beset with bristles; leaves 2 dm. long or more; marsh grass Reed Grass, Calamagrostis canadensis.
20c. Panicle spreading or somewhat contracted, but not spike-like; axis of the spikelet without bristles — 21.
21a. Panicle-branches erect or ascending — 22.  
21b. Panicle-branches strongly spreading — 23.
22a. The two outer scales of the spikelet one-fourth as long as the third scale, or sometimes one of them absent — 17a.
22b. The glumes at least half as long as the lemma Wood-grass, Muhlenbergia mexicana.
23a. The chief lateral branches of the panicle dividing and bearing flowers below their middle Red-top, Agrostis alba.
23b. The chief branches of the panicle dividing only beyond the middle Hair Grass, Agrostis hyemalis.
24a. Spikelets arranged in two rows to form a definite spike — 25.
24b. Spikelets in panicles, never in definite rows — 29.
25a. Spikelets in a single row on one side of the axis, forming a one-sided spike Yard Grass, Eleusine indica.
25b. Spikelets alternating on opposite sides of the axis, forming a two-rowed spike — 26.
26a. Spikelets in pairs at each joint, forming a dense spike (Wild Rye) — 27.
26b. Spikelets single at each joint, forming a loose, open or interrupted spike — 28.
27a. Glumes lanceolate Wild Rye, Elymus canadensis.
27b. Glumes narrowly subulate Wild Rye, Elymus virginicus.
28a. Spikelets with their edges toward the axis of the spike Rye Grass, Lolium perenne.
28b. Spikelets with their sides toward the axis of the spike Quack Grass, Agropyron repens.
29a. Glumes longer than the lemmas Oats, Avena sativa.
29b. Glumes shorter than the lemmas — 30.
30a. Axis of the spikelet beset with conspicuous long hairs about equaling the lemmas; tall marsh grass 1-4 m. high Reed, Phragmites communis.
30b. Spikelets without conspicuous long hairs — 31.
31a. Spikelets sessile or nearly so, forming crowded or spike-like panicles — 32.
31b. Spikelets distinctly panicled — 33.
32a. Spikelets in dense one-sided clusters at the ends of the panicle branches Orchard Grass, Dactylis glomerata.
32b. Spikelets in an erect spike-like cluster Prairie June-grass, Koeleria cristata.
33a. Lemmas, exclusive of the awn when present, 8 mm. long or more — 34.
33b. Lemmas, exclusive of the awn when present, 6 mm. long or less — 35.
34a. Awns on the lemmas 12 mm. long or more Brome-grass, Bromus tectorum.
34b. Awns on the lemmas 8 mm. long or less, or none Cheat, Bromus secalinus.
35a. Lemmas with 7 sharp conspicuous veins from base to apex Manna Grass, Glyceria nervata.
35b. Lemmas with 3-5 inconspicuous veins — 36.
36a. Spikelets with 5 flowers or more — 37.
36b. Spikelets with 2-4 (rarely 5) flowers — 40.
37a. Stems tufted and decumbent at base (Love Grass) — 38.
37b. Stems erect (Fescue Grass) — 39.
38a. Spikelets 1.5 mm. wide Love Grass, Eragrostis pilosa.
38b. Spikelets 3 mm. wide Love Grass, Eragrostis megastachya.
39a. Lemmas with conspicuous awns Fescue Grass, Festuca octoflora.
39b. Lemmas without awns Fescue Grass, Festuca elatior.
40a. Tufted annual grass Spear Grass, Poa annua.
40b. Perennials, with erect flowering stems — 41.
41a. Stems round Blue Grass, Poa pratensis.
41b. Stems strongly flattened Canadian Blue Grass, Poa compressa.


CYPERACEAE, the Sedge Family

Grass-like or rush-like plants, with linear leaves or leafless, and inconspicuous flowers in small chaffy spikes.

Over 200 species occur in Michigan, of which only the commonest are included here. For the remaining species the Manuals should be consulted.

1a. Spikes all alike — 2.
1b. The uppermost spike or spikes wholly staminate, the lower one or more pistillate; ovary and achene surrounded by a sac, the perigynium. Mature fruit is necessary for satisfactory identification (Sedge) — 12.
2a. Stems leafless, bearing one or more spikes at or near the top — 3.
2b. Stems leafy — 6.
3a. Spike one, terminal and erect (Spike Rush) — 4.
3b. Spikes usually more than one, lateral and spreading — 5.
4a. Annual, with fibrous roots Spike Rush, Eleocharis obtusa.
4b. Perennial, with a running rootstock Spike Rush, Eleocharis palustris.
5a. Stem round Bulrush, Scirpus validus.
5b. Stem 3-cornered Three-square, Scirpus americanus.
6a. Spikes axillary along the side of the stem Dulichium, Dulichium, arundinaceum.
6b. Spikes terminal — 7.
7a. Spikes subtended by long conspicuous leaves which greatly exceed the flower clusters — 8.  
7b. Spikes not conspicuously exceeded by the bract-like leaves — 10.
8a. Spikes in a dense head-like cluster, white-woolly at maturity Cotton Grass, Eriophorum virginicum.
8b. Spikes not in dense heads, nor white-woolly at maturity — 9.
9a. Perennial by a creeping rootstock Nut Grass, Cyperus esculentus.
9b. Perennial by hard basal corms Cyperus, Cyperus strigosus.
10a. Bracts of the spike chestnut-brown Twig Rush, Cladium mariscoides.
10b. Bracts of the spike green or straw-color (Sedge) — 11.
11a. Spikes 3-8, separate Sedge, Carex straminea.
11b. Spikes very numerous and densely crowded Sedge, Carex vulpinoidea.
12a. Achenes flattened Sedge, Carex crinita.
12b. Achenes 3-angled — 13.
13a. Perigynium tipped with a sharp straight 2-toothed beak — 14.
13b. Perigynium with a short soft beak — 17.
14a. Perigynium thin and papery, loosely enclosing the achene — 15.
14b. Perigynium firm, closely enclosing the achene — 16.
15a. Perigynium less than 1 cm. long Sedge, Carex hystericina.
15b. Perigynium more than 1 cm. long Sedge, Carex lupulina.
16a. Perigynium smooth Sedge, Carex riparia.
16b. Perigynium hairy Sedge, Carex filiformis.
17a. Beak of the perigynium bent abruptly to one side Sedge, Carex laxiflora.
17b. Beak of the perigynium straight Sedge, Carex pennsylvanica.


ARACEAE, the Arum Family

Individual flowers small, but crowded on a fleshy spadix to form a conspicuous spike, usually surrounded by a green or colored spathe.

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.


COMMELINACEAE, the Spiderwort Family

Leafy-stemmed herbs; flowers with 3 sepals, 3 petals, and 6 stamens, lasting but a single day; petals blue.

1a. Stamens 6; petals all equal (Spiderwort) — 2.
1b. Perfect stamens 3, sterile stamens 3; two of the petals larger than the third (3-6 dm. high; summer) Day-flower, Commelina virginica.
2a. Sepals villous (3-10 dm. high; late spring) Spiderwort, Tradescantia virginiana.
2b. Sepals glabrous, or with a tuft of hairs at the apex (4-10 dm. high; late spring) Spiderwort, Tradescantia reflexa.


PONTEDERIACEAE, the Pickerel-weed Family

Aquatic herbs, with 6 rather conspicuous petals; flowers in summer.

1a. Flowers blue; leaves cordate-sagittate (3-10 dm. high) Pickerel-weed, Pontederia cordata.
1b. Flowers yellow; leaves linear (submerged) Mud Plantain, Heteranthera dubia.


JUNCACEAE, the Rush Family

Grass-like or rush-like plants, with inconspicuous greenish or brownish flowers, of 3 chaffy or scale-like sepals and as many similar petals.

1a. Leaf-sheaths closed; capsule 1-celled and 3-seeded; stem or leaves usually hairy at or near the base (1-4 dm. high). (Wood Rush) — 2.
1b. Leaf-sheaths open; capsule many-seeded; plants never hairy — 4.
2a. Flowers solitary at the ends of the branches of the umbel-like cluster (spring) Wood Rush, Luzula saltuensis.
2b. Flowers in spikes or dense clusters — 3.
3a. Flower-cluster spike-like, nodding at the tip (summer) Wood Rush, Luzula spicata.
3b. Flower-cluster umbel-like (spring) Wood Rush, Luzula campestris var. multiflora.
4. The genus Juncus, or Rush, contains about 25 species in Michigan, blooming in summer or autumn. For their identification the Manuals should be consulted. One of the commonest species is Juncus effusus, growing in marshes, with erect leafless cylindrical stems, bearing a lateral cluster of flowers near the summit. Another common species is Juncus tenuis, with slender stems and linear leaves, growing in hard ground, especially in woodland paths.


LILIACEAE, the Lily Family

Herbs or twining shrubs, with generally conspicuous flowers; sepals and petals each 3, and usually colored alike, stamens 6, ovary 3-celled, superior. In one species the perianth is 4-parted and the stamens are 4.

1a. Flowers or flower-clusters lateral, axillary or apparently so — 2.
1b. Flowers or flower-clusters scapose or terminal — 12.
2a. Leaves minute and scale-like (7-15 dm. high; flowers greenish-yellow, June) Asparagus, Asparagus officinalis.
2b. Leaves broad and flat, not scale-like — 3.
3a. Flowers numerous in rounded umbels; perianth-segments nearly separate; leaves long-petioled — 4.  
3b. Flowers in clusters of 1-8; leaves short-petioled, sessile, or clasping — 8.
4a. Stems herbaceous (flowers greenish-yellow, ill-scented) (Carrion-flower) — 5.
4b. Stems woody, thorny, climbing (flowers greenish-yellow, early summer) (Green Brier) — 7.
5a. Stems climbing by tendrils — 6.
5b. Stem not climbing; only the upper leaves, or none, with tendrils Carrion-flower, Smilax ecirrhata.
6a. Leaves smooth beneath. Carrion-flower, Smilax herbacea.
6b. Leaves minutely pubescent beneath when mature Carrion-flower, Smilax herbacea var. pulverulenta.
7a. Leaves with 5 principal veins. Green Brier, Smilax rotundifolia.
7b. Leaves with 7 principal veins. Green Brier, Smilax hispida.
8a. Perianth-segments united into a tube (flowers axillary, late spring) (Solomon's Seal) — 9.
8b. Perianth-segments separate (2-8 dm. high; spring) (Twisted-stalk) — 10.
9a. Leaves minutely pubescent beneath; filaments rough, inserted at three-fourths the length of the perianth (3-8 dm. high) Small Solomon's Seal, Polygonatum biflorum.
9b. Leaves smooth beneath; filaments smooth, inserted at the middle of the perianth tube (5-15 dm. high) Great Solomon's Seal, Polygonatum commutatum.
10a. Leaves distinctly clasping the stem; flowers greenish-white Twisted-stalk, Streptopus amplexifolius.
10b. Leaves closely sessile; flowers reddish to purple — 11.
11a. Rootstock short and thick; berries spherical Twisted-stalk, Streptopus roseus.
11b. Rootstock long and slender; berries 3-angled Twisted-stalk, Streptopus longipes.
12a. Perianth-segments 5-12 cm. long — 13.
12b. Perianth-segments shorter than 5 cm. — 19.
13a. Leaves all or chiefly basal, stem-leaves bract-like or none — 14.
13b. Leaves chiefly or entirely on the stem — 15.
14a. Leaves numerous, linear or sword-shape (flowers orange, summer) Day Lily, Hemerocallis fulva.
14b. Leaves a single pair, oblong or lanceolate — 21.
15a. Leaves a single whorl of 3 (Wake Robin, Trillium) — 22.
15b. Leaves numerous (6-12 dm. high; flowers yellow, orange, or red, in summer) (Lily) — 16.
16a. Flowers erect — 17.
16b. Flowers nodding — 18.
17a. Leaves narrowly lanceolate, 6-15 mm. wide, mostly whorled Wood Lily, Lilium philadelphicum.
17b. Leaves linear, 5 mm. wide or less, almost all alternate Wood Lily, Lilium philadelphicum var. andinum.
18a. Perianth-segments strongly revolute Turk's-cap Lily, Lilium superbum.
18b. Perianth-segments half-recurved Yellow Lily, Lilium canadense.
19a. Flower solitary — 20.
19b. Flowers in clusters, not solitary — 31.
20a. Stem with a single pair of basal leaves (Dog's-tooth Violet) — 21.
20b. Stem with a single whorl of 3 leaves (1-3 dm. high; spring) (Wake Robin, Trillium) — 22.
20c. Stem leafy (Bellwort) — 29.
21a. Perianth yellow Dog's-tooth Violet, Erythronium americanum.
21b. Perianth white, bluish, or pinkish Dog's-tooth Violet, Erythronium albidum.
22a. Flower sessile, red or brown  — 23.
22b. Flower peduncled, white or pink, rarely red — 24.
23a. Leaves sessile, sepals spreading Wake Robin, Trillium sessile.
23b. Leaves short-petioled, sepals reflexed Wake Robin, Trillium recurvatum.
24a. Ovary with 6 distinct wing-like angles — 25.
24b. Ovary obtusely 3-angled or lobed — 28.
25a. Stamens distinctly longer than the pistil — 26.
25b. Stamens equaling or shorter than the pistil — 27.
26a. Stigmas erect or nearly so, slender Wake Robin, Trillium grandiflorum.
26b. Stigmas strongly recurved or spreading Wake Robin, Trillium erectum.
27a. Filaments about as long as the anthers Wake Robin, Trillium cernuum.
27b. Filaments half as long as the anthers or shorter Wake Robin, Trillium declinatum.
28a. Leaves obtuse; petals obtuse, white Dwarf White Trillium, Trillium nivale.
28b. Leaves acuminate; petals acute, purple-striped at base Painted Trillium, Trillium undulatum.
29a. Leaves sessile (3-6 dm. high; flowers yellow, spring) Bellwort, Oakesia sessilifolia.
29b. Leaves perfoliate (4-6 dm. high; flowers yellow, in spring) — 30.
30a. Leaves minutely pubescent beneath Bellwort, Uvularia grandiflora.
30b. Leaves glabrous and all glaucous Bellwort, Uvularia perfoliata.
31a. Stem bearing 2 whorls of 3-9 leaves (3-6 dm. high; flowers pale yellow, early summer) Indian Cucumber-root, Medeola virginiana.
31b. Stem-leaves not whorled, or all leaves basal — 32.
32a. Flowers in umbels — 33.
32b. Flowers in racemes or panicles — 38.
33a. Plant with the odor of onions or garlic (leaves all or chiefly basal; flower-stalks 2-8 dm. high, late spring or summer) — 34.
33b. Plant not with the odor of onions (leaves basal; flower-stalks 2-3 dm. high, with an umbel of 3-6 greenish-yellow flowers in late spring) Clintonia, Clintonia borealis.
34a. Leaves oblong, 2-5 cm. wide, not present when the plants are in bloom (greenish-white flowers) Wild Leek, Allium tricoccum.
34b. Leaves linear, present with the flowers — 35.
35a. Umbel nodding or horizontal (petals rose-color) Wild Onion, Allium cernuum.
35b. Umbel erect — 36.
36a. Pedicels longer than the flowers — 37.
36b. Pedicels equaling or shorter than the flowers (petals rose-purple) Wild Chives, Allium schoenoprasum var. sibiricum.
37a. Leaves flattened; flowers pink to white Wild Onion, Allium canadense.
37b. Leaves cylindrical; flowers greenish to purple Field Garlic, Allium vineale.
38a. Leaves lanceolate to ovate, not more than 8 times as long as broad — 39.
38b. Leaves linear or grass-like, at least 12 times as long as broad — 45.
39a. Principal leaves all basal, stem-leaves none or bract-like — 40.
39b. Principal leaves on the stem — 41.
40a. Flowers in a spike-like raceme (4-10 dm. high; small white flowers in summer) Colic-root, Aletris farinosa.
40b. Flowers in an umbel-like cluster — 34b.
41a. Perianth-segments 4 (1-2 dm. high; flowers white, early summer) Wild Lily of the Valley, Maianthemum canadense.
41b. Perianth-segments 6 — 42.
42a. Styles 3; flowers dioecious (3-10 dm. high; flowers white, early summer) Blazing Star, Chamaelirium luteum.
42b. Style 1; flowers perfect, white, in spring (False Solomon's Seal) — 43.
43a. Flowers panicled (3-6 dm. high) False Solomon's Seal, Smilacina racemosa.
43b. Flowers racemed — 44.
44a. Leaves 2-4, usually 3 (1-2 dm. high) False Solomon's Seal, Smilacina trifolia.
44b. Leaves 5-12 (2-5 dm. high) False Solomon's Seal, Smilacina stellata.
45a. Flowers bright blue; perianth-segments united (2-3 dm. high, spring) Grape Hyacinth, Muscari botryoides.
45b. Flowers blue, greenish, yellowish, or white; perianth-segments separate — 46.
46a. Flowers 1 cm. wide, or smaller (white or greenish, in racemes, late spring or summer) (False Asphodel) — 47.
46b. Flowers 1.5 cm. wide, or larger — 48.
47a. Stem glabrous (2 dm. high or less) False Asphodel, Tofieldia palustris.
47b. Stem viscid-pubescent (1-5 dm. high) False Asphodel, Tofieldia glutinosa.
48a. Perianth-segments with 2 glands near the base (3-8 dm. high; greenish-white panicled flowers in summer) Zygadenus, Zygadenus chloranthus.
48b. Perianth-segments without glands — 49.
49a. Plant 3-5 dm. tall; flowers blue or nearly white, in long racemes (early summer) Wild Hyacinth, Camassia esculenta.
49b. Plant 1-3 dm. tall; flowers greenish-white, in short corymb-like racemes (spring) Star of Bethlehem, Ornithogalum umbellatum.