There are several indigenous species of Epilobium, which have the common name of willow-herb, from the resemblance of their leaves to the willow, all of which probably have nearly identical properties. The E. Angustifolium is the largest of them. Its leaves and roots are said to be demulcent, tonic, and astringent. They are used by the eclectics, generally and locally, in. decoction, infusion, or cataplasm, as astringents. Oliver reports (B. M. J., 1897, ii) violent poisoning with epileptiform convulsions caused by B. hirsutum L. Under the name of Kaporie tea, the leaves of E. angustifolium and of E. hirsutum are largely used in Russia as a beverage.

Gerard calls it: 'A goodly and stately plant having leaves like the greatest willow or osier, garnished with brave flowers of great beautie, consisting of four leaves apiece of an orient purple colour." It is a native of most countries of Europe. In this country, it has apparently become more common than it was in Gerard's day. He tells us he had received some plants of this species from a place in Yorkshire, apparently as a rarity, 'which doe grow in my garden very goodly to behold, for the decking up of houses and gardens.'

It is to be found by moist riversides and in copses, but will sometimes spring up in a town, self-sown, on waste ground recently cleared of buildings: the site of Kingsway and Aldwych in London, adjoining the Strand, where many buildings, centuries old, had been pulled down, was the following summer covered by the Rose Bay Willow-herb, as by a crimson mantle, though no one could explain where the seeds had come from. The same phenomenon was repeated, in Westminster, when other old buildings were demolished for improvements and the ground remained waste for a considerable time. In America, it springs up on ground recently cleared by firing, being one of the plants called 'Fireweed' in the United States where it is known as the Great or Spiked Willow-herb, Bay Willow, Flowering Willow, Purple Rocket, Wickup and Wicopy.

The plant is in bloom for about a month. The individual flowers are about an inch in diameter, calyx and corolla each four-parted; the stamens, eight in number, standing up, form an arch or dome over the ovary, on the green, fleshy, upper surface of which nectar is secreted. Sprengel, in 1790, showed that the flowers, which open soon after sunrise, are protenandrous, i.e. the anthers ripen first, and self-pollination would occur if insects did not visit them. Bees, who much visit the flowers in search of nectar, get smeared by the pollen, which is sticky. It is not left by them on the stigma of the same flower, however, which at this stage is a mere knob, immature and unable to receive the pollen grains. On reaching another flower, further advanced, the stigma, ripe for reception of pollen, has opened out to become a white, four-rayed cross of great distinctness and perforce receives any pollen the insect visitor may have collected as he pushes by to get to the nectar below, and the ovules thus become fertilized.

The dead flowers, when fertilization has been effected, fall off cleanly from the long, projecting, quadrangular pods, which later split into four long strands, which stretch wide apart, disclosing a mass of silky white hairs, in which are embedded the very tiny seeds, a few hairs being attached to the top of each seed. The slightest wind scatters them broadcast over the neighbourhood. All the Willow-herbs distribute their seeds in the same manner, and as the plant spreads extensively by creeping stems it is very difficult to keep it within bounds.

Uses. The leaves of the Rose Bay Willow herb have been used as a substitute and adulterant of Tea. Though no longer so employed in England, the leaves of both this species and of the Great Hairy Willow-herb (E. hirsutum, Linn.) are largely used in Russia, under the name of Kaporie Tea.

Medicinal Action and Uses. The roots and leaves have demulcent, tonic and astringent properties and are used in domestic medicine in decoction, infusion and cataplasm, as astringents. Used much in America as an intestinal astringent. The plant contains mucilage and tannin.

By some modern botanists, this species is now assigned to a separate genus and designated: Chamaenerion angustifolium (Scop.).