=ROBÍNIA.= The Locusts.
=Robinia Pseùdo-Acàcia= Linnæus. Locust. Black Locust. Plate 109. Medium
sized trees with deeply furrowed bark; twigs at first green and hairy,
becoming at the end of the season glabrous and a light brown, the
stipules developing in about a year into a pair of woody spines about 2
cm. long; leaves pinnate, 1.5-3 dm. long; leaflets 7-17 on short stalks,
ovate to oblong, 2-6 cm. long, rounded at base, rounded or pointed and
with a small indenture at apex, margin entire, pubescent on both sides
at first, becoming at maturity glabrous above and remaining more or less
pubescent below, especially on the midrib; flowers in loose racemes,
white, expanding in May or June; fruit a flat and slightly curved pod
about 5-10 cm. long, glabrous; seeds usually 4-8 in each pod, about 4
mm. long and 2.5 mm. wide; wood heavy, very hard, close-grained, takes a
good polish, very durable in contact with the soil.
=Distribution.=--Appalachian Mountains from Pennsylvania south to
northern Georgia, and in Arkansas. In Indiana it is found as an escape
in all parts and was doubtless native along the Ohio River, at least in
the southeastern part of the State. Thomas[59] says: "We had gazed at
the majestic beech of this country (near Rising Sun) three feet in
diameter; we had seen the honey locust, the black walnut, a buckeye of
equal magnitude; and then we saw with surprise, the black locust almost
a rival in stature." Drake[60] says: "The flowering locust is abundant
in Kentucky. Along the Ohio River it is rarely found more than 30 miles
north of the river."
=Remarks.=--This tree is generally known as the locust tree, but is
sometimes called the yellow locust.
Locust wood is somewhat lighter than white oak, but it is 34 percent
stiffer and 45 per cent stronger. These remarkable qualities added to
its durability in contact with the ground make it one of the most
desirable trees for forest planting. The wood has been used principally
for posts, ties, tree nails, etc. The locust when grown close together
usually grows to 8-12 inches in diameter. There are, however, specimens
that have grown in the open that are almost three feet in diameter. The
pioneers used it extensively for ornamental planting, and it has escaped
from such planting in all parts of the State. It propagates easily by
root shoots which is the principal mode of spreading, except where the
seed fall on exposed soil.
[Illustration: Plate 109.