BIRCH FAMILY 
stipulate. Apparently they often appear in pairs, but these 
pairs are really borne on spur-like two-leaved lateral 
branchlets. 
The flowers are monoecious, opening with 
or before the leaves and borne in_three- 
flowered clusters in the axils of the scales of 
drooping or erect aments. Staminate aments 
are pendulous, clustered or solitary in the 
axils of the last leaves of the branch of the 
year or near the ends of the short lateral 
branchlets of the year. They form in early 
autumn and re- 
main rigid dur- 
ing the winter. 
The scales of 
the staminate 
aments when 
mature are broadly ovate, 
rounded, yellow or orange 
Branch of Red Birch, 
Betula nigra, Show- 
dark chestnut brown at ing the Staminate 
color below the middle, 
Aments as they Ap- 
apex. Bach scale bears “™e% ey"? 
two bractlets and three 
sterile flowers, each flower consisting of a 
pear in Winter. 
sessile, membranaceous, usually two-lobed, 
calyx. Each calyx bears four short fila- 
ments with one-celled anthers or strictly, 
two filaments divided into two branches, 
each bearing a half-anther. Anther cells 
open longitudinally. The pistillate aments 
are erect or pendulous, solitary ; terminal 
Four Staminate and One 
pistillate Ament of Ol the two-leaved lateral spur-like branch- 
Sweet Birch, Betula lets of the year. The pistillate scales are 
lenta. Staminate 
Ament 340 ACNE oblong-ovate, three-lobed, pale yellow green 
often tinged with red, becoming brown at 
maturity. These scales bear two or three fertile flowers, 
each flower consisting of a naked ovary. The ovary is 
296 
