This section is from the book "Nature's Garden", by Neltje Blanchan. Also available from Amazon: Nature's Garden; An Aid To Knowledge Of Our Wild Flowers And Their Insect Visitors.
Stem: 1 to 2 ft. high, erect, much branched. Leaves: Small, opposite, oblong, more or less black-dotted. Preferred Habitat - Fields, waste lands, roadsides. Flowering Season - June - September. Distribution - Throughout our area, except the extreme North;
Europe, and Asia.
"Gathered upon a Friday, in the hour of Jupiter when he comes to his operation, so gathered, or borne, or hung upon the neck, it mightily helps to drive away all phantastical spirits." These are the blossoms which have been hung in the windows of European peasants for ages on St. John's eve, to avert the evil eye and the spells of the spirits of darkness. " Devil chaser" its Italian name signifies. To cure demoniacs, to ward off destruction by lightning, to reveal the presence of witches, and to expose their nefarious practices, are some of the virtues ascribed to this plant, which superstitious farmers have spared from the scythe and encouraged to grow near their houses until it has become, even in this land of liberty, a troublesome weed at times. "The flower gets its name," says F. Schuyler Mathews, "from the superstition that on St. John's day, the 24th of June, the dew which fell on the plant the evening before was efficacious in preserving the eyes from disease. So the plant was collected, dipped in oil, and thus transformed into a balm for every wound." Here it is a naturalized, not a native, immigrant. A blooming plant, usually with many sterile shoots about its base, has an unkempt, untidy look; the seed capsules and the brown petals of withered flowers remaining among the bright yellow buds through a long season. No nectar is secreted by the St. John's-worts, therefore only pollen collectors visit them regularly, and occasionally cross-fertilize the blossoms, which are best adapted, however, to pollinate themselves.
The Shrubby St. John's-wort (H. prolificum) bears yellow blossoms, about half an inch across, which are provided with stamens so numerous, the many flowered terminal clusters have a soft, feathery effect. In the axils of the oblong, opposite leaves are tufts of smaller ones, the stout stems being often concealed under a wealth of foliage. Sandy or rocky places from New Jersey southward best suit this low, dense, diffusely branched shrub which blooms prolifically from July to September.
Farther north, and westward to Iowa, the Great or Giant St. John's-wort (H. Ascyron) brightens the banks of streams at midsummer with large blossoms, each on a long footstalk in a few-flowered cluster.
Shrubby St John's Wort. (Hypericum prolificum.)