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Hypericum perforatum

L. (1753)

This name is accepted

Kingdom: Viridiplantae Phylum: Magnoliophyta Class/Clade: Eudicot-Rosids Order: Malpighiales Family: Hypericaceae Genus: Hypericum

klamath weed, St. John's wort

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Description

Key Characters:

Growth Form: Rhizomatous perennial herbs.

Stems: Stems 1 to several, erect, becoming somewhat woody toward base, 5–10 dm long, black–dotted.

Roots:

Leaves: Leaves simple. Opposite. Blades linear to elliptic or oblanceolate; primary ones 10–30 mm long, 3–16 mm wide. Surfaces usually black–dotted. Margins entire. Sessile. Stipules absent.

Flowers: Flowers in paniculate cymes. Flowers bisexual (perfect). Sepals connate at base, the lobes lanceolate, 3–5 mm long, glandular punctate. Petals obovate, 5–8 mm long, black–dotted along margins. Stamens numerous, in 3 clusters. Ovary superior; styles 3(4).

Fruit: Capsules ovoid; 7–8 mm long. Seeds dark brown; cylindrical; ca. 1 mm long; the surface pitted.

Ploidy: 2n = 32; 34; 36; 48

Habitat:

Elevation Range:

Historical Distribution

Images

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Uses and Culture

USES

  • Yes

Natural History

Statewide Status

Naturalized

Island Status

Maui Only found in cultivation
Hawai'i Extirpated

Dispersal Agents

Other Animals

Vegetative Reproduction

Pollinators

Specimens

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Bibliography

Name Published In: Sp. Pl.: 785 (1753)

Other References

Wagner et al. 1990:546 (H); Carlson s.n. BISH 11353 (H†, 1964)

Occurrences

SNo. Scientific Name Locality Habitat Basis of Record Description Recorded By Record Number Island Source Date
1 Hypericum perforatum Morgan Toledo Taro Farm, Waipio Valley, Big Island, Hawaii OBSERVATION Curtis Daehler Hawaii HAPI 7/19/2007
2 Hypericum perforatum East Maui, purchased form Lowe's Garden Shop, Kahului Garden shop. Preserved_Specimen Sprawling, ascending herb; lvs oblong, opposite, w. black glands along margins of undersides, 1-2cm long; flowers also w. black glands on petal edges & stamens, petals ca. 8mm long; no fruit seen. Starr, F. 208021 Maui BISH 2002-08-02
3 Hypericum perforatum Hualalai Preserved_Specimen a weed (European) Carlson, N.K. Hawaii BISH 1964-07-01
4 Hypericum perforatum Kaupulehu Road up Hualalai, North Kona Colony in grazed flat Preserved_Specimen Erect, fls yellow. Fosberg, F.R. 42087 Hawaii BISH 1961-09-09
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