(Capsella Bursa Pastoris).
"Shepherd's Purse" is so called on account of its purse-like seed pods. There is only one species of this plant, which is said to be found almost all over the world and flowering nearly the whole year round. It is a very common, ubiquitous weed. Do not sow this in your garden, or you will never get it out again. You will find it growing there in all probability without sowing it. In poor soil it attains the height of a few inches only, but in rich soil it becomes a strong plant 2 ft. in height. The plant is green, but somewhat rough with hairs; the lower leaves are pinnatifid (that is, a number of leaves are arranged along the opposite sides of the leaf-stalk); the leaves of the stem are oblong and arrow-shaped at the base. The odour of the plant is rather unpleasant. The flowers are numerous, small, white, followed by wedge-shaped fruit pods, divided by narrow partitions into two cells, which contain the oblong seeds. This common weed, which causes the farmer and gardener to talk, is very valuable asa medicinal agent. In fact, it is a remedy of the first importance in catarrhal conditions of the bladder and ureters, also in ulcerated conditions and abscess of the bladder. It is diuretic—that is, it increases the flow of urine. Its use is specially indicated when there is white mucous matter voided with the urine; relief is usually very quick.
Dr. Ellingwood, in his valuable work on Therapeutics, says of Shepherd's Purse:—"This agent has been noted for its influence in hematuria - . . . soothing irritation of the renal or vesical organs. In cases of uncomplicated chronic menorrhagia (excessive menstruation) it has accomplished permanent cures, especially if the discharge be persistent and devoid of much colour. The agent is also useful where uric acid or insoluble phosphates or carbonates produce irritation of the urinary tract. Externally, the bruised herb has been applied to bruised and strained parts, to rheumatic joints, and where there was ecchymosis or extravasations within or beneath the skin.
"The herb is rather unpleasant to take, but it is valuable mixed with Pellitory of the Wall, and a little Spirits of Juniper much disguises the flayour. A small quantity of Nitrate of Potash will further disguise it, and not detract from its medicinal value. The infusion may be taken in wineglassful doses four times a day."
Common Plants and their Uses in Medicine was written by Richard Lawrence Hool, F.N.A.M.H., in 1922.