This section is from the book "British Wild Flowers - In Their Natural Haunts Vol2-4", by A. R. Horwood. Also available from Amazon: A British Wild Flowers In Their Natural Haunts.
The present distribution of this plant, which is the limit of our knowledge so far as to its antiquity and range, is the North Temperate Zone, where it is found in Europe, N. Africa, Siberia, W. Asia, and it has been introduced into N. America. In Great Britain it is abundant in all the counties except Cardigan, Carnarvon, Stirling, Mid Perth, S. Aberdeen, Banff, Elgin, Easterness, W. and N. Highlands, West Sutherland, and the Northern Isles.
The Great Hairy Willow Herb grows wherever there is a moist ditch, or by pond-sides, along the margins of lakes and rivers, and in marshes and pools. It is a gregarious plant, needing constant moisture at the roots, but may rarely be found on dry land. With it grow other Willow Herbs, Flags, Reeds, Sedges, and a host of other hygrophytes in the reed swamp.
Though without so conspicuous a flower as the Rosebay, it is a taller, more abundant gregarious plant, and has so delicious a scent that it is equally popular. It is tall, erect, branched, with underground stolons or creeping shoots, with the upper leaves lance-shaped, alternate, clasping, very woolly, like the stem (hence the second Latin and the English names), and slightly bordered with small teeth.
Numerous and large, the flowers are purple, bell-shaped, and partly drooping. The white anthers are long and awl-shaped. The calyx is deeply divided, angular, erect, finely hairy inside below. The petals are inversely heart-shaped, white at the base, and twice as long as the calyx. The flowers are regular, with erect style and stamens. The tuberculate pale - brown seeds, downy one side, enclosed in a pod, are acute below.
The Great Hairy Willow Herb forms dense brakes 6 ft. high. The flowers are in bloom during July and August. The plant is a herbaceous perennial, and freely reproduced by roots or stoles. The flowers are large, being 25-30 mm. across, and make a good show when growing in a clump. The stigmas and anthers ripen together, and the plant is capable of self-pollination. But cross-pollination is ensured by insect visitors by the more prominent position of the stigmas. In the absence of insects the stigmas curl back and touch the pollen of the longer stamens. Insect visitors are not very numerous. Other forms occur in which there are large flowers in which the anthers are mature first. The pistil is long and pendent, and self-pollination is out of the question. In still others the flower is of a medium size, and the anthers may ripen slightly in advance of the stigma, or simultaneously with the latter. There are also flowers of a third type which are small, and in which the stigma and anthers mature at the same time, and in this case the plant is usually self-pollinated. There are pistillate plants with no pollen on the anthers. The seeds, as in the Rosebay, are provided with a tuft of hairs which aid in wind dispersal.
Photo. H. Irvine - Great Hairy Willow Herb (Epilobium Hirsutum, L.)
Photo. Flatters & Garnett - Great Hairy Willow Herb (Epilobium Hirsutum, L.)
The Great Hairy Willow Herb is essentially arenophilous, addicted to a sand soil. But it grows largely in alluvium, which is sandy loam with some humus.
A rust fungus, Puccinia pulverulenta, is the chief fungal pest, but Sphaerotheca humuli attacks Willow-herbs generally.
The Lepidoptera, Bedstraw Hawk-moth (Deilephilagalii), Sericoris urticana, Laverna lactella, L. propinquella, L. ochracella, L. epilobiella, the Gothic (Naenia typica), Small Elephant Hawkmoth (Chaerocampa elpenor), Lygris lugubrata, feed on this sweet-scented flower.
The second Latin name hirsutum refers to the downy1 stem and foliage.
It is called Coddled Apple, Apple-pie, Blooming Sally, Cherry-pie, Codlins, Codlings-and-cream, Custard-cups, Fiddle-grass, Gooseberry Pie, Plum-pudding, Sod-apple, Son-before-the- Father, Wild Willow, Willow Herb, Red Withy-herb.
From its smell it is called Plum-pudding, Apple-pie, Cherry-pie, Gooseberry Pie, and Sod-apple. As to the name Son-before-the-Pather, Lyte says: "It is called of some, in Latine, Films ante Patrem, that is to say, the sonne before the father, bycause yt has long huskes in which the seede is coteined do come forth, and waxe great, before that the flouere openeth".
Essential Specific Characters:119. Epilobium hirsutum, L. - Root creeping, stem tall, branched, leaves opposite, downy, lanceolate, serrate, clasping, flowers puce, regular, stamens and style erect, stigma 4-cleft.