240 WOODY PLANTS OF MASSACHUSETTS. 
day, as they were anciently in Italy, the best food for cows, 
goats and horses. 
Both willows and poplars are remarkable for the size and 
length of their roots, for their fondness for water, and for their 
tenacity of life. All the species of both genera are easily propa- 
gated by cuttings ; and most of them, planted by river sides, scrve, 
like the alders, to protect the banks from being worn away by 
the action of the stream; and, from the rapidity of growth, and 
the hardiness of many of the species, they are admirably adapt- 
ed to act as nurses to more tender trees in exposed situations. 
The family is distinguished by the following characters :—The 
sterile and fertile fowers are on distinct plants. Both are dis- 
posed in many-flowered aments, each flower being supported 
by a bracteal scale. The ovaries are solitary and one-celled, 
with many ovules. The stigmas are two. The {rut is a one- 
celled, many-seeded capsule, opening with two valves. The 
seeds are very minute, erect, attached to the inner surface of 
the valves, and circled by a tuft of very long, cottony down. 
The leaves are alternate. 
The genera are two, the Poplar, and the Willow. They are 
distinguished by the general appearance of their leaves, which, 
in the poplar, are roundish or triangular in outline; in the wil- 
low, usually long and narrow; and by the number of stamens, 
which are from two to seven in the willow, and from eight to 
thirty or more in the poplar, and set in a little cup protected by 
a jagged scale. 
VI. 1. THE POPLAR. POPULUS. 1. 
The poplars are large trees, with alternate leaves, and, while 
young, a smooth, leather-hke bark. The buds are more or legs 
invested with a fragrant, viscid balsam. The leaves are large, 
roundish or triangular in outline, and set upon a long footstalk, 
which is laterally compressed towards the leaf, whence the 
leaves have their characteristic, tremulous motion when agitated 
by the wind. The footstalks are often set with glands. The 
flowers come out before the leaves, from scaly buds. They 
are disposed in cylindrical aments, and composed each of a 
scale deeply cut or torn at the edge. Beneath each scale in the 
