Identifying characteristics:
The honey locust is a fast-growing tree with a short trunk and an open,
spreading crown, often identified in the wild by its smooth, sharp, branched
thorns on the trunk and branches. The once- or twice-pinnately compound,
alternately-arranged leaves are
a glossy, bright green, with each leaflet having tiny, widely-spaced teeth
along the margins. The leaves turn yellow-green or clear yellow and fall
early in autumn. The small, fragrant, greenish-white flowers
are produced in May or June, male and female flowers often on separate branches.
Cuttings from branches with only male flowers produce podless trees more
favorable for landscaping purposes. The fruit
is a twisted pod, 6 to 8 inches long and 1 inch wide, containing 12 or more
seeds. Pods ripen in autumn but may persist on the tree, falling in winter
without opening. The small, irregularly-shaped leaf scars each contain 3
bundle scars. The buds are embedded in the leaf scar and twig, with
only the tips visible. A terminal bud is absent. The bark
of young trees is gray, separating into long, flat ridges slightly upturned
at the end. Older trees develop a darker, deeply furrowed bark.
Similar species:
Ecology:
Distribution: The honey locust is common in the midwestern and south
central US on floodplains and in limestone soils. It is native to southern,
eastern and central Iowa and is widely planted throughout the state. Agriculture
has created an ideal habitat in Iowa where this tree has become a pasture
and fencerow weed.
Habitat: Although intolerant of shade, the honey locust is extremely
adaptable and tolerant of drought, high pH and saline conditions. Diseases
and pest infestations have dramatically increased in areas where continuous
plantings of this tree occur, with mimosa webworm, borers and several fungal
cankers becoming the primary problems. Leaf spot, witches' broom, powdery
mildew, rust, midge pod gall and spider mite are also reported.
Uses:
Wood: The reddish-brown wood is hard, strong, heavy, shock
resistant and durable. It is used for fence posts, railroad ties and fuel.
Wildlife: The name "honey locust" comes from the sweet, honey-like pulp inside the pods, which is eagerly eaten by grazing cattle, dispersing the seeds in the process. White-tailed deer, rabbits, squirrels and quail also eat the pulp of the pods.
Horticulture: Once an excellent ornamental lawn tree, the honey locust has become overused since the Dutch elm disease initiated a search for a replacement tree for the American elm (Ulmus americana). The honey locust produces a light shade that allows grass to grow up to the stem, is long-lived, adaptable and easy to transplant. Some varieties are thornless ('Inermis' and 'Moraine') and others are podless ('Green Glory' and 'Halka'). 'Sunburst' is a golden-leafed variety, but is susceptible to canker.
