Field Marks: The distinguishing features of the hedge-hyssops are the low growth form, the opposite leaves, and the small flowers with 2 tiny bracts near the calyx, and 2 stamens. The clammy hedge-hyssop differs from other hedge-hyssops by its tapering leaf bases and slender flower stalks at least 1/2 inch long.
Habitat: Marshes, wet woods, roadside ditches, along streams, ponds, and lakes, wet fields.
Habit: Annual herb with fibrous roots.
Stems: Erect or spreading, branched or unbranched, hairy, less than 1 foot long.
Leaves: Opposite, simple, lanceolate to oblanceolate, short-pointed at the tip, tapering to the base, somewhat hairy, up to 1 1/2 inches long.
Flowers: Solitary in the axils of the leaves, white or yellowish, up to 1/2 inch long, on slender stalks at least 1/2 inch long.
Sepals: 5, free or nearly so, green.
Petals: 5, united below into a yellowish tube, the lobes white.
Stamens: 2.
Pistils: Ovary superior.
Fruits: Capsules ovoid, up to 1/4 inch long, containing many seeds.