A 
/ 
4 


_ With deeply-cut foliage, and slender, graceful growth. Recently introduced. 



8 _ TREES AND SHRUBS 
portance, being too small, though under certain circumstances it is durable 
enough, sj. 
oh. 
Alnus firma, Siebo/d and Zuccarini. Branching, thick-trunked shrub, — 
from Japan. “ag 
Alnus glutinosa, Wil/denow. EUROPEAN ALDER. ‘Tree from Europe, 
30 to 40 feet high, rapid grower, and said to be hardy. It has the following 
varieties: *imperialis asplenifolia. IMPERIAL FERN-LEAVED ALDER. 
ww 
. ] > 
- ese 

laciniata. Cur-LEAVED ALDER. Large and handsome; showy leaves, 
deeply cleft. Hardy.. . ; 
* Alnus maritima, A/vhlenderg. SEASIDE ALDER. Small tree, growing 
along streams in Delaware and Maryland; flowers in September, fruit de- 
velops next season; leaves oblong, with a wedge-shaped base, green or rusty 
on lower surface. eg 
Alnus serrulata, 47ton. SmMooTH ALDER. A mere shrub, 6 feet high. 
The common Alder of the Northern States as far west as Wisconsin. 
Betula. Bircu. Has 3 sterile flowers under each scale; 4 stamens, each 
with a I-celled anther; 2 to 3 fertile flowers under.a 3-lobed scale; seed with 
a broad wing. 
Betula alba, Z7zn@us. WHITE BircH. Tree of northern parts the world 
around. 50 to 60 feet high; outer bark white, readily separated. A striking 
tree in grounds. There are the following varieties in the Park: pendula. 
With slender, drooping branches. From this, again, we have the garden 
forms laciniata, with delicately-cut leaves,and Youngii. populifera, Spach, 
is our Middle State form, has slender leaf-stalks, which cause the very long 
pointed leaves to tremble in the slightest breeze. Tree 15 to 20 feet high. 
purpurea. PurRpPLE-LEAVED BIRCH. With a rich purple-colored foliage. 
pyramidalis. PyRAMIDAL BircH. A slender, spire-like variety, with a 
rich green foliage. 
Betula lenta, Z7zn@us. CHERRY BIRCH, SWEET or BLACK BIRCH. Native 
tree of good size, with clear dark-brown bark and a rose-colored timber which 
is valuable in cabinet-work ; heart-shaped leaves, closely double-toothed ; scales 
of the fruiting flower-clusters “ with short divergent lobes.” 
Betula lutea, J/ichaux the younger. YELLOW or GRAY BircH. (Betula 
excelsa of American authors.) A good-sized native tree, with yellow or gray 
bark peeling off in thin layers; wood white, and of less importance than that 
of the preceding species; leaves slightly, if at all, heart-shaped. 
Betula nigra, Z7nnzus. RIVER or RED Bircu. (Betula nigra, Michaux 
the younger.) <A large tree, ranging from Massachusetts southward and west- 
ward; wood light-colored, and leaves resembling those of the Alder. 
Betula papyracea, 4‘ton. PAPER or CANOE BirRCH. A large tree, with 
close-grained wood and strong bark which peels easily and which is used in 
making the birch-bark canoes of the Northern waters. This species ranges 
widely over the northern parts of the Continent, reaching sparingly into Penn- 
sylvania. 
