Guttiferae - St. Johnís-wort family
 

WeedsPoisonous PlantsHay Fever
Gerald A. Mulligan (Agriculture Canada, Ottawa, retired)
Hypericum perforatum L., St.John's-wort, millepertuis commun
Perennial, spreading by seeds, and by shoots from underground runners; apomictic; flowering stems 1 to 3 feet (1 to 9 dm.) high; yellow flowers with black dots around the edges; mostly absent from the mid-west, but common elsewhere; pastures, meadows, roadsides, and waste places; introduced from Europe. Grazing by livestock can cause photosensitization, resulting in sickness or even death.

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Weed Name Photo Weed Name Photo
St.John's-wort, millepertuis commun St.John's-wort, millepertuis commun
(winter)
St.John's-wort, millepertuis commun
(shoots from underground runners)
St.John's-wort, millepertuis commun
(seedling)
St.John's-wort, millepertuis commun (NC) St.John's-wort, millepertuis commun (plants)
St.John's-wort, millepertuis commun
(F&M)