=BETULÀCEAE.= The Birch Family.
Trees or shrubs with simple, petioled, alternate (in pairs on the older
branches of _Betula_) leaves; staminate flowers in long drooping
catkins, 1-3 in the axil of each bract, the pistillate in short lateral
or terminal aments; fruit a nut or samara.
Staminate flowers solitary in the axil of each bract,
without a calyx, pistillate flowers with a calyx;
nut wingless.
Bark of tree smooth; staminate aments in winter enclosed
in bud scales; nut exposed, its subtending bract
more or less irregularly 3-cleft 1 Carpinus.
Bark of older trees shreddy; staminate aments in winter
naked; nut enclosed in a bladder-like bract 2 Ostrya.
Staminate flowers 3-6 in the axil of each bract, with a
calyx, pistillate flowers without a calyx; nut winged.
Winter buds sessile; stamens 2; fruit membranous and
hop-like; fruiting bract deciduous at the end of
the season when the nut escapes 3 Betula.
Winter buds stalked; stamens 4; fruit woody and
cone-like; fruiting bracts woody and persisting
after the nuts escape 4 Alnus.
=1. CARPÌNUS.= The Hornbeam.
=Carpinus caroliniàna= Walter. Water Beech. Blue Beech. Plate 30. A
small tree up to 3 dm. in diameter, usually 1-1.5 dm. in diameter with
fluted or ridged trunks; bark smooth, close, gray; twigs hairy at first,
soon becoming glabrous; leaves ovate-oblong, average leaves 6-10 cm.
long, pointed at the apex, double-serrate, hairy when young, glabrous at
maturity except on the veins and in the axils beneath, pubescent, not
glandular, staminate catkins appearing in early spring; nut at the base
of a 3-cleft bract about 2 cm. long, nut broadly ovate, compressed,
pointed and about 5 mm. long; wood heavy, hard, tough and strong.
=Distribution.=--Nova Scotia west to Minnesota and south to Florida and
Texas. In Indiana it is frequent to common throughout the State in moist
rich woods. It prefers a moist rich soil; however, it has a range from
the tamarack bog to the dry black and white oak slope. It is tolerant of
shade and is seldom found outside of the forest.
=Remarks.=--This tree is too small and crooked to be of economic
importance. It is regarded as a weed tree in the woodland, and should be
removed to give place to more valuable species.
[Illustration: Plate 30.