This same little tree is called also the glaucous willow, and it is botanically _Salix discolor_. It is more distinct than some others of the family, for the willow is a great mixer. The tree expert who will unerringly distinguish between the red oak and the scarlet oak by the precise angle of the spinose margins of the leaves (how I admire an accuracy I do not possess!) will balk at which is crack willow, or white willow, or yellow or blue willow. The abundant vigor and vitality and freedom of the family, and the fact that it is of what is known as the dioecious habit--that is, the flowers are not complete, fertile and infertile flowers being borne on separate trees--make it most ready to hybridize. The pollen of the black willow may fertilize the flower of the white willow, with a result that certainly tends to grayness on the worrying head of the botanist who, in after years, is trying to locate the result of the cross!
[Illustration: Blossoms of the white willow]
There is much variety in the willow flowers--and I wonder how many observers really notice any other willow "blossoms" than those of the showy pussy? A superb spring day afield took me along a fascinatingly crooked stream, the Conodoguinet, whose banks furnish a congenial and as yet protected (because concealed from the flower-hunting vandal) home for wild flowers innumerable and most beautiful, as well as trees that have ripened into maturity. An earlier visit at the time the bluebells were ringing out their silent message on the hillside, in exquisite beauty, with the lavender phlox fairly carpeting the woods, gave a glimpse of some promising willows on the other side of the stream. Twilight and letters to sign--how hateful the desk and its work seem in these days of springing life outside!--made a closer inspection impossible then, but a golden Saturday afternoon found three of us, of like ideals, hastening to this tree and plant paradise. A mass of soft yellow drew us from the highway across a field carpeted thickly with bluet or "quaker lady," to the edge of the stream, where a continuous hum showed that the bees were also attracted. It was one splendid willow in full bloom, and I could not and as yet cannot safely say whether it is the crack willow or the white willow; but I can affirm of a certainty that it was a delight to the eye, the mind and the nostrils. The extreme fragility of the smaller twigs, which broke away from the larger limbs at the lightest shake or jar, gave evidence of one of Nature's ways of distributing plant life; for it seems that these twigs, as I have previously said, part company with the parent tree most readily, float away on the stream, and easily establish themselves on banks and bars, where their tough, interlacing roots soon form an almost impregnable barrier to the onslaught of the flood. Only a stone's throw away there stood a great old black willow, with a sturdy trunk of ebon hue, crowned with a mass of soft green leafage, lighter where the breeze lifted up the under side to the sunlight. Many times, doubtless, the winds had shorn and the sleet had rudely trimmed this old veteran, but there remained full life and vigor, even more attractive than that of youth.