Northern Prairie Wildlife Research Center
Southern Wetland Flora
Field Office Guide to Plant Species
Dotted St. Johnswort
Hypericum punctatum Lam.
- Family: St. Johnswort (Hypericaceae)
- Flowering: June-September
- Field Marks: The distinctive features of this St. Johnswort are the black-dotted leaves and petals
and the capsules about 1/4 inch long.
- Habitat: Old fields, moist woods, thickets, prairies, along roads.
- Habit: Perennial herb with a rather woody base.
- Stems: Upright, sparsely branched, smooth, black-dotted, up to 2 1/2 feet tall.
- Leaves: Opposite, simple, elliptic to oblong, rounded or slightly pointed at the tip, rounded at
the sessile or clasping base, without teeth, smooth, black-dotted with 5 or 7 veins, up to
2 1/2 inches long, up to 2/3 inch wide.
- Flowers: Several, borne in cymes, on stalks up to 1/8 inch long; each flower about 1/2 inch
- Sepals: 5, green, free from each other, ovate to oblong, black-dotted or black-lined, up to
1/8 inch long.
- Petals: 5, yellow, free from each other, black-dotted, up to 1/4 inch long.
- Stamens: Numerous, borne in clusters of 5.
- Pistils: Ovary superior; styles 3, free from each other.
- Fruits: Capsules ovoid, glandular, up to 1/4 inch long; seeds yellow.
Previous Species -- Orange-grass (Hypericum gentianoides)
Return to Species List -- Group 7
Next Species -- Creeping Seedbox (Ludwigia repens)