Form and size: The locust is a medium-sized tree developing a slender
straight trunk when grown alongside of others; see Fig. 82.

Range: Canada and United States.

Soil and location: The locust will grow on almost any soil except a wet,
heavy one. It requires plenty of light.

Enemies: The _locust borer_ has done serious damage to this tree. The
grubs of this insect burrow in the sapwood and kill the tree or make
it unfit for commercial use. The _locust miner_ is a beetle which is
now annually defoliating trees of this species in large numbers.

Value for planting: It has little value for ornamental planting.

Commercial value: Though short-lived, the locust grows very rapidly. It
is extremely durable in contact with the soil and possesses great
strength. It is therefore extensively grown for fence-posts and
railroad ties. Locust posts will last from fifteen to twenty years.
The wood is valuable for fuel.

[Illustration: FIG. 82.--Black Locust Trees.]

Other characters: The _flowers_ are showy pea-shaped panicles appearing
in May and June. The _fruit_ is a small pod.

Other common names: _Yellow locust_; _common locust_; _locust_.

Comparisons: The _honey locust_ (_Gleditsia triacanthos_) can be told