Hypericum

Scientific name

Hypericum L.

Common names

pale St. John's-wort, elliptic-leaved St. John's-wort, creeping St. John's-wort, few-flowered St. John's-wort

Family

Hypericaceae/Clusiaceae

Similar genera

Cuphea, Epilobium, Lindernia, Lysimachia, Macbridea, Mentha, Mimulus, Veronica

Native distribution

eastern North America

Species cultivated

not currently cultivated

Adventive distribution

information not available

Weed status

not weedy

Habit

amphibious, emergentemergent:
(adj) (syn. emersed) with parts raised out of the water; extending up out of the water
, or temporarily submergedsubmerged:
(adj) (syn. submersed) under water; submerged below the water surface
small to medium stem plant

Brief description

Rhizomes prominent. Stem erect, simple or with few branches, slightly 4-angled, glabrousglabrous:
(adj) without hairs or scales
. Leaves oppositeopposite:
(adj) (of leaves) two leaves per node; in pairs on opposite sides of an axis
, decussatedecussate:
(adj) arranged along stem in pairs, with each pair at right angles to the pairs above and below
; sessilesessile:
(adj) attached directly, without a stalk
; leaf bladeblade:
(n) (syn. lamina) the flat, expanded part of a leaf, frond, or petal (excluding, e.g., the petiole)
simple, oval to elliptic; apexapex:
(n) the point farthest from the point of attachment; the tip (often pointed)
obtuse; base cuneatecuneate:
(adj) wedge-shaped; triangular, with narrow end at the base
; margins entireentire:
(adj) having a continuous margin that is not toothed or lobed
. Inflorescenceinflorescence:
(n) the arrangement of flowers on the floral axis
a terminalterminal:
(adj) at the apex
and/or subterminal cymecyme:
(n) a determinate, usually flat-topped or convex inflorescence in which the terminal flower blooms earliest
. Flowers nearly sessilesessile:
(adj) attached directly, without a stalk
, typically 5-merous, yellow. Sepals oblanceolate-obovate, apexapex:
(n) the point farthest from the point of attachment; the tip (often pointed)
obtuse, slightly shorter than petals, persistentpersistent:
(adj) (of leaves etc,) remaining attached; not being dropped or falling off
; petals ellipticelliptic:
(adj) in the form of an ellipse (oval)
to oblongoblong:
(adj) two to four times longer than wide, with +/- parallel sides
, apexapex:
(n) the point farthest from the point of attachment; the tip (often pointed)
obtuse; stamens numerous, yellow; carpels 3, styles 3 united below, stigmasstigmas:
(n) the portion of the pistil that is receptive to pollen
minute.

Natural habitat

moist sandy soil; shores of rivers, streams, and lakes, marshes, swamps, bogs, wetland margins, wet ditches, meadows and fields

Additional comments

Hypericum contains over 450 species. H. ellipticum Hook. is an amphibiousamphibious:
(adj) of a plant able to live on land or in water
species. A sterilesterile:
(adj) lacking male and/or female reproductive parts; not producing fruit, seed, pollen, spores, etc.
submersed form is known, which has simple stems and feather-veined leaves.