MALVACEAE, the Mallow Family
Herbs with alternate leaves; sepals and petals each 5; stamens numerous, united by their filaments to form a tube surrounding the styles; ovary many-celled.
| 1a. Flowers yellow (summer and autumn) [— 2.] | |
| 1b. Flowers pale-yellow, with a dark center (2-4 dm. high; late summer) | Flower-of-an-hour, Hibiscus trionum. |
| 1c. Flowers white to red or blue, never yellow [— 3.] | |
| 2a. Leaves broadly heart-shape (10-15 dm. tall) | Velvet Leaf, Abutilon theophrasti. |
| 2b. Leaves ovate-lanceolate (2-5 dm. tall) | Sida, Sida spinosa. |
| 3a. Calyx subtended by 6 to many bractlets which are sometimes united at base (summer) [— 4.] | |
| 3b. Calyx subtended by 3 bractlets, or by none [— 6.] | |
| 4a. Flowers 2-4 cm. wide (5-10 dm. high; flowers pink) | Marsh Mallow, Althaea officinalis. |
| 4b. Flowers 7-15 cm. wide (8-15 dm. high; flowers pink to nearly white) (Rose Mallow) [— 5.] | |
| 5a. Leaves densely pubescent below | Rose Mallow, Hibiscus moscheutos. |
| 5b. Leaves glabrous | Rose Mallow, Hibiscus militaris. |
| 6a. Petals prominently notched at the end or reverse heart-shape (Mallow) [— 7.] | |
| 6b. Petals obtuse or truncate (summer) [— 11.] | |
| 7a. Flowers 1-1.5 cm. wide [— 8.] | |
| 7b. Flowers 2-5 cm. wide (3-8 dm. high; flowers in summer) [— 9.] | |
| 8a. Stems procumbent, prostrate, or spreading (spring, summer, and autumn) | Mallow, Malva rotundifolia. |
| 8b. Stems erect (10-15 dm. high; summer) | Mallow, Malva verticillata. |
| 9a. Leaves with prominent but shallow lobes; flowers axillary | Mallow, Malva sylvestris. |
| 9b. Leaves deeply lobed or cleft; flowers in the upper axils, producing a raceme-like cluster [— 10.] | |
| 10a. Lobes of the leaf dentate or incised | Mallow, Malva alcea. |
| 10b. Lobes of the leaf pinnately cleft into linear or narrowly oblong divisions | Mallow, Malva moschata. |
| 11a. Flowers white (1-2 m. high) | Virginia Mallow, Sida hermaphrodita. |
| 11b. Flowers purple or pink (3-5 dm. high, spreading) | Poppy Mallow, Callirhoe triangulata. |
HYPERICACEAE, the St. John's-wort Family
Herbs or shrubs, with opposite entire leaves dotted with translucent glands; flowers usually yellow (or pink); sepals and petals each 5; stamens 5 to many; ovary with 3-5 styles. (St. John's-wort.)
| 1a. Shrubs (4-8 dm. high; flowers yellow, summer) [— 2.] | |
| 1b. Herbs (flowers in summer) [— 3.] | |
| 2a. Styles 5 | St. John's-wort, Hypericum kalmianum. |
| 2b. Styles 3 | St. John's-wort, Hypericum prolificum. |
| 3a. Flowers pinkish, 15 mm. broad (3-5 dm. high, in swamps) | Marsh St. John's-wort, Hypericum virginicum. |
| 3b. Flowers yellow [— 4.] | |
| 4a. Flowers about 4 cm. wide; principal leaves 5-10 cm. long (7-15 dm. tall) | St. John's-wort, Hypericum ascyron. |
| 4b. Flowers 8-25 mm. wide; stamens 15 or more [— 5.] | |
| 4c. Flowers 1-10 mm. wide; stamens 12 or fewer (1-6 dm. high) [— 7.] | |
| 5a. Petals dotted with black (4-8 dm. high) [— 6.] | |
| 5b. Petals without black dots (2-5 dm. high) | St. John's-wort, Hypericum ellipticum. |
| 6a. Flowers 20-25 mm. wide; leaves of an oblong type, broadest near the middle | St. John's-wort, Hypericum perforatum. |
| 6b. Flowers 10-15 mm. wide; leaves of an ovate type, broadest below the middle | St. John's-wort, Hypericum punctatum. |
| 7a. Leaves minute, subulate, 1-3 mm. long | Pineweed, Hypericum gentianoides. |
| 7b. Leaves linear, with 1-3 principal veins, broadest near or above the middle | St. John's-wort, Hypericum canadense. |
| 7c. Leaves lanceolate, 4-6 times as long as broad, with 5-7 principal veins | St. John's-wort, Hypericum majus. |
| 7d. Leaves oblong, elliptic, or ovate, 1.5-3 times as long as broad [— 8.] | |
| 8a. Uppermost bracts linear | St. John's-wort, Hypericum mutilum. |
| 8b. Uppermost bracts resembling the leaves in shape, but smaller | St. John's-wort, Hypericum boreale. |
ELATINACEAE, the Waterwort Family
Small marsh herbs, with opposite leaves without translucent dots, and inconspicuous axillary flowers. (Stems 2-5 cm. long; flowers in summer.)
| One species in Michigan | Waterwort, Elatine americana. |