712 POPLAR tree of the far west, that many suppose it to be a peculiarly western species ; it is found in New England, and extends quite across the conti- nent, being very abundant in the valley of the Mississippi, and on the otherwise treeless plains beyond is found marking the courses of rivers and small streams. It derives its specific name from the fruiting aments, which are very long, and with the unopened capsules upon them have some resemblance to a string of beads. The tree grows 80 ft. or more high ; the wood is very difficult to split, the fibres being so in- terlaced, and though of very poor quality, it is made, in localities where this is the only large wood procurable, to serve a variety of purposes. It is called cottonwood from the great abun- dance of down upon the seeds, and in planting it for shade special care should be taken to set cuttings from the staminate tree only. The narrow-leaved cottonwood, P. angustifolia, is a far western tree, found growing with the common cottonwood, and by some considered as a variety, as it resembles it in everything except its leaves, which are ovate-lanceolate, sometimes acute, and slightly serrate. The angled cottonwood, P. angulata, has more an- gular branches and larger leaves than the true cottonwood, and is supposed to be a mere va- riety of it ; another form, known in the west- ern states as yellow cottonwood, oan only be distinguished by the color of its heart wood, which is yellowish ; it splits more freely, warps much less, and is more durable than the ordi- nary cottonwood. The American aspen, P. tremuloides, so named from its general resem- blance to the European P. tremula, is a grace- ful tree 20 to 50 ft. high and quite common in woods, especially northward and in Canada; it shows in a marked degree the tremulous motion of the leaves, which are round-heart- shaped, with small regular teeth ; the trunk has a smooth greenish white bark. This is regarded as a short-lived tree of no special use. The large-toothed aspen, P. grandidentata, receives its name from the large, irregular, wavy teeth to its leaves, which are larger than in the one preceding, and, though smooth when full grown, are at first very downy on both sides ; it is also a larger tree with a gray bark. Its timber, which has considerable strength, is durable if kept dry, and is employed for inte- rior work ; in states where it is abundant it is used for fences, being cut of the proper length, split, and nailed to posts ; if felled in summer and peeled, it makes a durable fence stuff, but if left with the bark on it speedily decays. A weeping variety is known in the nurseries as P. grandidentata pendula ; it has its branch- es as distinctly pendulous as those of the weeping willow, and when grafted upon a stock of Lombardy poplar, some 10 or 12 ft. high, it grows rapidly and makes one of the most beautiful of lawn trees. The downy poplar, P. Jieterophylla, has its leaves covered with white wool when young ; it is a large tree of no special interest, found in swampy lands from New England to Illinois. The balsam poplar, P. lalsamifera, is a large tree, also called tackmahack, found from New England to Wisconsin and northward ; it has ovate, ta- pering, and pointed leaves, and the large leaf buds are covered with abundant varnish ; the tree is of no special use. Its variety called balm of Gilead (P. balsamifera, var. candi- cans) differs from the species in having broad- er and more or less heart-shaped leaves, with somewhat hairy petioles ; it has a similar range with the preceding ; it is rare in the wild state, but not uncommon in cultivation. Some 30 years ago it was a popular tree to plant for shade, and for the pleasant fragrance given off by its buds in spring; it suckers badly, and is much infested by insects. A tincture, made by putting the buds into spirit, was formerly a popular remedy for chronic rheumatism and pulmonary complaints ; the resin of the buds is apparently a stimulant, similar to the tur- pentines and balsams. Among the European species the most common in cultivation is the white poplar, P. alba, which is quite as fre- quently called abele, a name introduced with the tree from Holland into England ; the Dutch name abeel is said to be from the Latin albel- lus, whitish, a name given to the tree by some ancient writers. All these names refer to the marked character of the tree, the persistent white color of the under sides of the leaves ; the white cottony down does not as in most species disappear with age, but as the leaves grow older the contrast between the dark green of the upper and almost snowy white- ness of the lower surface becomes stronger. White Poplar or Abele (Populus alba). The tree is a rapid grower ; it has an ash-gray bark and a somewhat regular dense head ; it was at one time very popular, but its defects having been discovered, it is now as much de- cried as it was formerly praised ; in its ap- propriate place it is a most valuable tree, but that is not upon a lawn or in cultivated grounds, as it throws up suckers in great num-
