common st. john’s-wort

Hypericum perforatum

Member of st. john’s worts (genus Hypericum)
st. john’s worts tribe (tribe Hypericeae)
st. john’s wort family (family Hypericaceae)
dicots (class Magnoliopsida)
yellow in flowering plants

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• herb
• leaf narrowly oblong, not folded, tip obtuse
• sterile axillary branches generally 2–10 cm
• petals 8–12 mm
• the only local member is ssp. perforatum

Toxicity of hypericum, klamath weed, st. john's wort (Hypericum perforatum):
1 – Skin contact with these plants can cause symptoms ranging from redness, itching, and rash to painful blisters like skin burns.
3 – Ingestion of these plants is expected to cause nausea, vomiting, diarrhea and other symptoms that may cause illness but is not life-threatening.

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Chris’s observations: 10 (4 are research grade)

Locations:

• Sanborn CP: 4
• Skyline Ridge OSP: 2
• Wilder Ranch SP: 2
• Bear Creek Redwoods OSP
• Castle Rock SP

Months:

• Jun.: 4
• Jul.: 5
• Aug.: 0
• Sep.: 1

For more details, use advanced search.

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Taxon info: iNaturalist – Calflora – CalPhotos – Jepson eFlora – FNA

Bay Area species: iNaturalist – Calflora