Besides the White Poplar or Abele tree there are two other Poplars which are fairly common in this country. One is the Lombardy Poplar, which grows tall and slender like a church spire; its branches rise upward like the flame of a torch, and the tree trunk is clothed to the very ground with withered branches, which never spread outwards, but grow close to the main stem. There is no difficulty in recognising the Lombardy Poplar. The Black Poplar is also common in many parts of Britain. Its leaves are not lined with white; they are heart-shaped, with no jagged edges, but with dainty little teeth cut evenly all round. The heads of the stamens, which grow in groups on the catkin tail, are very dark purple, and they hang from the end of twigs, which are rough with the scars of last year’s leaves. PLATE XIV THE ASPEN “Variable as the shade By the light, quivering aspen made.” --Scott. The Aspen (1) is a member of the Poplar family, and in many ways it resembles its cousins. But you will always know an Aspen tree by its leaves (2). These are never still unless when a storm is brooding and the air is perfectly calm; at all other times they shake and quiver incessantly, and you can hear the gentle rustle they make as each leaf rubs against its neighbour. In the Scottish Highlands the country people tell you that the Aspen trembles because at the Crucifixion the cross of Christ was made of Aspen, and the tree must always shudder at the recollection of the cruel purpose it served. [Illustration: PLATE XIV THE ASPEN 1. Aspen Tree 2. Leaf Spray 3. Stamen Catkins 4. Seed Catkin] The Aspen is usually found growing in copses, or in meadow lands, where it flourishes best in a damp soil; but it is also found on mountain ground, and is very common in the north of Scotland. It is not a long-lived tree: the heart of it begins to decay after fifty or sixty years, just at the age when many of our most familiar trees are at their finest. The wood is very soft, and is of little use either for building or for manufacturing purposes; but it is beautifully white, and sculptors use it for decorative carving; also many of the wooden blocks required by engravers for printing are made of Aspen wood. The Aspen is one of our catkin-bearing trees. Early in spring you will see dangling on the branches long fluffy tails, which you must pluck and examine carefully. There are two kinds of flowering catkins on the Aspen, and both kinds may be found growing on the same tree. Sometimes you find them close beside each other on the same branch.