Locust trees are relatively easy to identify once you know what to look for. There are several key characteristics that can help you determine if a tree is a locust tree, specifically a honey locust or a black locust.
1. Leaf Appearance:
– Honey Locust: The leaflets of a honey locust leaf are narrower and more elongated, being more than twice as long as they are wide. They have a more lanceolate shape, tapering at both ends. The leaflets are usually arranged in a pinnate compound leaf, meaning there are multiple leaflets attached to a central stem.
– Black Locust: In contrast, black locust leaves have more rounded leaflets. While still compound leaves, the leaflets of black locust are broader and shorter compared to honey locust. The leaflets may have a slightly oval or elliptical shape.
2. Leaflet Count:
– Honey Locust: Honey locust leaves tend to have an even number of leaflets attached to the central stem. You may find 8 to 14 leaflets per leaf, depending on the age and health of the tree.
– Black Locust: Black locust leaves typically have an odd number of leaflets, ranging from 9 to 19. There is always a single leaflet at the end of each leaf, which can be helpful in distinguishing it from honey locust.
3. Bark and Trunk:
– Honey Locust: The bark of a mature honey locust tree is usually grayish-brown and has deep furrows and ridges. The trunk tends to be rougher and more textured compared to black locust.
– Black Locust: Black locust trees have dark gray to brown bark that is deeply furrowed, but the ridges are often smoother compared to honey locust. The trunk may appear more solid and sturdy.
4. Flowers and Fruits:
– Honey Locust: Honey locust trees produce small greenish-yellow flowers in the spring, which are inconspicuous and clustered in elongated clusters called catkins. These flowers eventually give way to long, flat, and twisted seed pods that can hang on the tree throughout the winter.
– Black Locust: Black locust trees also produce small white flowers in the spring, arranged in large drooping clusters. These flowers have a sweet fragrance and attract pollinators. After flowering, black locust trees develop thick, dark brown seed pods that contain several small seeds.
5. Growth Habit and Habitat:
– Honey Locust: Honey locust trees typically have a spreading, rounded crown and can reach heights of 30 to 70 feet. They are commonly found in open areas, including parks, lawns, and along roadsides.
– Black Locust: Black locust trees have a more upright and narrow growth habit, with a height ranging from 30 to 80 feet. They are often found in disturbed areas, such as old fields, fence rows, and abandoned lots.
Identifying a locust tree, whether it is a honey locust or a black locust, involves carefully observing the leaf characteristics, such as shape, size, and leaflet count, as well as examining the bark, flowers, and fruits. By paying attention to these details and comparing them to the descriptions provided, you will be able to confidently identify the type of locust tree you are encountering.
