Speckled John. Introduced. Perennial. Propagates by seeds and by runners from the base of the stem. Time of bloom: June to September. Seed-time: July to October. Range: Throughout British America except in the far North, and in all the states except the most southern. Habitat: Fields, pastures, and waste places.
A most pernicious weed, difficult of suppression. When young its juices are so acrid and blistering that no grazing animal will eat the plant; and when mature or dried in hay, stock reject it because of its woody toughness. (Fig. 199.)
Fig. 199. - Common St. John's-wort (Hypericum perforatum). X 1/4 an inch long, light green, sessile, more or less black-dotted and specked all over with pellucid dots. Flowers in terminal cymose clusters, very showy; petals five, golden yellow, nearly a half-inch long, with black-dotted margins; stamens many, separated into three groups, their anthers black-dotted; styles three, divergent; calyx of five lance-shaped, acute sepals, specked with pellucid dots. Capsule ovoid, three-celled, filled with small, rounded, oblong seeds, their surface delicately pitted in rows. Too often an impurity among grass seeds.
The plant is best destroyed by hand-pulling when the soil is sufficiently soft to slacken its hold on the long, woody roots. Or it may be grubbed out, care being taken to leave no stray runners. A meadow or a pasture too rankly infested to be so cleansed should be turned under and put to a well-tilled hoed crop.