112 FARM WEEDS OF CANADA 



THE ST. JOHN'S-WORT FAMILY {Hypericaceae). 



Herbs and shrubs of some 200 species, widely distributed 

 over the northern hemisphere, mostly in warm climates, represent 

 this family. The leaves are opposite, without teeth or divisions, 

 oblong or lance-shaped, dotted, usually stalkless. Flowers regular, 

 with many divisions, terminal, solitary or disposed in single or 

 compound cymes, commonly yellow. The common name, 

 St. John's-wort, comes from the use of plants of that family 

 in Europe as decoration on St. John's Day. 



COMMON ST. JOHN'S-WORT {Hypericum 'perforatum L.) 



Other English names: Amber, Penny-John, Rosin, Rose, 

 Herb-John. 



Introduced from Europe. Perennial by runners at the 

 woody base of the erect, much-branched, somewhat 2-edged 

 stem. Leaves opposite without teeth or divisions, elliptic or 

 linear oblong, black-dotted along the margin like the corolla 

 divisions. Flowers deep yellow, grouped into terminal, loose 

 cymes. 



The seeds (Plate 74, fig. 50) are borne in 3-celled, ovoid 

 pods. They are about 1/25 of an inch long, cylindrical, 

 rounded at the ends, with a minute point. The surface is 

 rough, pitted, a little shiny, dark brown to black in colour. 



Time of flowering: June to September; seeds ripe by July. 



Propagation : By seeds and rootstocks. 



Occurrence: Common in pastures, old meadows and road- 

 ways, from Nova Scotia to Ontario. 



Injury: This weed and some of its allied species are trouble- 

 some in fields and pasture lands. 



Remedy: Close cutting several times during the summer 

 will reduce it in pastures. An application of salt a small 



