The wood especially that of the White Willow (Salix alba), is made into paper pulp, besides affording the best charcoal for artists' crayons; whilst, not to mention the undoubted value of the bark for tanning purpose. The wood of the Crack Willow (Salix fragilis) being durable, light, and pliant, is used for wash-boards to mills, and for the bottoms of carts and barrows, and, though seldom now so employed, was long ago recommended by Matthew both for house-timbers and for naval purposes. Its roots yield a purple dye, which is used in France and Sweden for coloring Easter eggs. Of the early spring-tide beauties of the clear lemon-yellow and blood-red shoots, or the later charm of the shimmering reflection of "hoar leaves in the glassy stream," we may speak presently. But it is at first desirable to discriminate, at least to some extent, the objects of our admiration; and this the botanist finds a task so difficult, as almost to be abandoned in despair.
It will be remembered that Willows are "dioecious." Though belonging mainly to the Arctic and North Temperate zone, there are a few Willows in temperate South America and South Africa; and the species are very diverse in the situations, or "habitats," which they frequent. Thus, while Osiers are almost confined to spots where their roots are liable to be soaked with flood-waters, and many other species are fond of moisture, the Sallows, such as Salix caprea, flourish in dry woods and hedgerows, and several species inhabit the barren tops of Alpine mountains, or the equally barren plains of Arctic latitudes. So, too, do they vary in size, from the White Willow (S. alba), a tree sometimes eighty feet in height, the Crack Willow (S. fragilis), and the Bedford Willow (S. russelliana), which attain an equal, if not greater, height, with a girth of as much as twenty feet, down to the prostrate S. reticulata, under two feet in height, and the still smaller S. herbacea, the most diminutive of this type shrub.
The species belonging to Vitisalix, which include the large trees of the group, produce their leaves and flowers simultaneously, the flower-stalks bearing fully-developed leaves, and the catkin-scales being of a uniform, generally pale color. The filaments of the stamens are perfectly free from one another, and are hairy on the lower part, while the capsules are free from hairs; and the leaves are "convolute"--i.e., rolled together in the bud, like a scroll of paper, with one free edge. Those belonging to Caprisalix--shrubs and small trees, among which are most kinds of Osier--have no stalk to the catkin in the flowering stage, and have only small leaf-like bracts, or none at all, at the base of the catkin. The catkin-scales are generally discolored at their tips, and the male flowers have but two stamens each. In the fruiting stage the catkin sometimes becomes stalked, the stalk falling off with the catkin, as is also generally the case in the previous section. It is, perhaps, necessary to caution the tyro against confusing the catkin, which is made up of many flowers, with a single flower. Finally, the diminutive species belonging to the Chamelyx--the "Ground" Willows, as the name signifies--also have only two stamens; but their catkins are on long, leafy, terminal, or sub-terminal, shoots, which do not fall with the catkins.
The first sub-section of Vitisalix, Lycus--having from four to twelve, but generally five, stamens, includes the Bay-leaved Willow (S. pentandra) and the possible hybrid, the Shrewsbury S. cuspidata. The Bay-leaved Willow is a beautiful many-stemmed shrub, six or eight feet high, or a tree of twenty feet. The young bark is brown, harmonizing with the broad, polished leaves, whose fragrance gives the plant its name; and the species is noticeable on the banks of our northern rivers as the latest of the Willows in flowering.
Of the Diandrae, the sub-series Fragiles and Albae correspond to Linnaeus's species S. fragilis, the Crack Willow, and S. alba, the White Willow. The first of these two groups has "semi-cordate" stipules, stalked capsules, and forked stigmas, and includes S. fragilis, S. decipiens, and S. russelliana, which differ mainly in the character of the young bark and of the leaves. S. fragilis has very smooth, yellow-brown twigs, that are brittle in spring, and "elliptic-lanceolate" leaves, sometimes six inches long. S. decipiens has smooth orange or crimson twigs, turning to a reddish-brown, and leaves sometimes not over three inches in length. These two forms, though commonly pollarded as Osiers, will grow into trees as large as the beautiful Bedford Willow (S. russelliana), which has smooth, green, flexible twigs, and long tapering leaves, very glaucous on their lower surfaces.
The sub-series Albae, characterized by its minute, ovate-lanceolate stipules, its nearly sessile capsules, and its recurved stigmas, includes the White, or Huntingdon, Willow (S. alba), the Blue Willow (S. carulea), and the Golden Willow (S. vitellina). These grow into large and useful timber trees, distinguished from the last-mentioned group by having their branches not smooth, but silky, and without the tendency to break off at the base which gives their name to the Crack Willows. The silky hairs on the olive-green twigs of the Huntingdon Willow, with the leaves silky also on both surfaces, give the tree a weird appearance, which has earned it the name of the "White tree." It is often pollarded, but will grow into a fine tree if allowed, reaching a height of fifty feet, with a girth of six, in eighteen years. The Blue Willow has the leaves smooth on the upper surface when old, and glaucous, but not very silky, beneath; and the Golden Willow has bright yellow or reddish twigs, but slightly silky, and leaves which also become smooth, and are often not more than two inches long.
The Triandrae, having three stamens, include the French Willow (S. triandra) and its related forms, the Almond-leaved Willow (S. amygdalina), S. Hoffmaniana, and S. undulata, all of which are used as Osiers, though they will grow to twenty feet or more.
The sub-section Helice is distinguished by "equitant" folding of the leaves--each leaf being doubled longitudinally over the next, as if astride it--by purple anthers, which become black, and by united stamens, to which it owes the name Synandrae. It includes the Purple Osier (S. purpurea), the Red Osier (S. rubra), and the Rose Willow (S. helix). The dark-colored bark of the tough, but slender and drooping boughs of the first of these is well known; whilst the last-named has long been recognized by botanists from its crowded tufts of leaves, like green roses, caused by the punctures of a gall-fly.
The sub-section Vimen, with two distinct filaments, yellow anthers, a longish style, and a silky under-surface to the leaves, includes the Common Osier (S. viminalis) and other closely-related forms. The leaves on the long, slender, wand-like branches of the Osier are sometimes as much as ten inches long, and have their margins rolled back and slightly wavy. The catkins appearing long before the foliage--generally in April--form much of the golden "palm"-boughs of Easter.
The only remaining forms of any considerable size or importance, however, are the Sallow (S. cinerea) and the Goat Willow (S. caprea), belonging to the series Caperae These agree in having elliptical, wrinkled, dark-green leaves, more or less covered with short, curling hairs, and having two kidney-shaped stipules, whilst the style is very short or absent, and the capsule has a slender stalk. The Sallow is a large shrub, or small tree, fifteen to thirty feet high, frequenting damp situations. It is typically distinguished from the Goat Willow, into which some of its varieties graduate, by its downy buds and twigs, and glaucous "obovate-lanceolate" leaves, with reddish-brown hairs on their under-surfaces, and with large stipules.
The Goat Willow, frequenting drier situations, is a small tree, with smooth buds, and large, broad "ovate" leaves, having wavy margins with rounded serrations.
The detail necessary for their discrimination proves the ornamental value of many of the forms of Willow to be almost equal. The Almond-leaved, the Bay-leaved, and the Crack Willows, producing their bright golden flowers and graceful foliage simultaneously, are well worth planting by the water-side, as is also the Common Osier, on account of the elegant outline of its long leaves. In the bare-boughed, moist month of February, the glossy, brightly-colored young twigs of many kinds have a peculiar charm; but we have too often to be content to see the larger sorts in the grotesquely-maltreated form of pollards:--
"The shock-head Willows, two and two."
It is, however, when growing to its full natural stature, and reflected in the clear water of a river, by whose margin the Purple Loosestrife flames, and the Meadowsweet foams in creamy luxuriance, that the White or Bedford Willows are seen to the best advantage.