314 Trees for Shade and Ornament 
States, hence thoroughly hardy, with short oval scalloped foliage, and 
makes a good hedge plant. 
The two best known buckthorns, which, like the above, are either 
shrubs or small (twelve feet) trees, are two exotics from Europe and 
Asia, both entirely hardy, even in Manitoba: 
R. cathartica Linn. (310), Hartshorn, with sharply toothed, small, 
slightly scalloped leaves, is usually thorny. 
R. Frangula Linn. (311), with dark green shining foliage of the same 
size (one to three inch) as the preceding, but entire, forms a handsome 
lawn shrub or an excellent hedge plant, with its attractive fruit, red, 
changing to black. Its variety R. asplenzfolia (311@) excels in its dis- 
tinctive feathery foliage. 
WILLOWS 
Salix. This is one of the largest genera, with some hundred species 
and an endless number of varieties of medium to small-sized trees, but 
mainly shrubs, of wide range in all parts of the world. Their orna- 
mental value is not sufficiently appreciated. The fine, graceful foliage, 
mostly narrow elliptical, gives to the willows a place as an ornament 
peculiarly their own, and especially along borders of watercourses or 
near water scenes, where they are in their natural environment, they pro- 
duce a translucent, airy effect which heightens the lucidity of the water. 
There is enough variety of shade to be found in the foliage of the 
various willows to permit most pleasing effects to be produced by the 
grouping of this tribe alone. The bright yellow catkins of some, 
the white, silvery ‘‘pussies” of others, lend transient interest; while 
the bright yellow and red branches of some give pleasing winter effects, 
and the weeping forms of others are useful in their places. Tyranspiring 
profusely, they are useful in correcting swampy conditions, and their 
value in binding embankments and sand dunes is well known. They 
are rapid growers, but usually short-lived, and light-needing. In 
nature they are generally found near watercourses, but they are 
adaptive to dry soils, and most easily grown from mere poles, sprouting 
readily and responding to pruning. There are unfortunately a number 
of insects preying on willows. Some species of willows form suckers 
undesirably and are generally aggressive, propagating by broken 
twigs sprouting. Although their short life reduces their value, their 
ready sprouting habit and exceeding rapidity of growth permits ready 
