Trees that produce distinctive, elongated structures often resembling large bean pods can capture attention in various landscapes. These structures are the tree’s fruit, botanically known as legumes or capsules. Identifying these trees involves recognizing the unique characteristics of their pods and other features.
Common Trees Bearing Pods
The Honey Locust tree (Gleditsia triacanthos) has prominent, flat, and often twisted pods. These pods range from 7 to 18 inches long and are dark brown to purplish-black when mature. They have a leathery texture and contain several hard, oval seeds embedded in a sticky pulp.
The Black Locust (Robinia pseudoacacia) produces shorter, flatter pods compared to its honey locust relative. These smooth, reddish-brown pods are 2 to 4 inches long and remain on the tree through winter. Each pod contains four to eight small, kidney-shaped seeds.
The Kentucky Coffeetree (Gymnocladus dioicus) has stout, flattened pods that are dark brown to reddish-brown and have a leathery texture. These large pods, measuring 4 to 10 inches long and 1 to 2 inches wide, persist on the branches through winter. Inside, they contain several hard, dark brown seeds surrounded by a sticky, greenish pulp.
Catalpa trees (Catalpa speciosa and Catalpa bignonioides) have long, slender, bean-like capsules up to 20 inches. These green pods mature to dark brown and persist on the tree through winter, splitting open to release numerous flat, winged seeds. The pods often hang in clusters, creating a distinctive appearance.
The Redbud tree (Cercis canadensis) produces small, flattened, reddish-brown to purplish pods about 2 to 4 inches long. These pods resemble miniature pea pods and are found abundantly along the tree’s branches. Each pod contains small, flattened, disc-shaped seeds.
Distinguishing Characteristics
Honey Locust trees have fine, fern-like, doubly compound leaves, and their trunks often display sharp, branched thorns. The bark is dark brown and deeply furrowed. Black Locust trees have pinnately compound leaves with oval leaflets and have pairs of short, sharp thorns at the base of their leaves.
Kentucky Coffeetrees have doubly compound leaves, which are among the largest of any temperate tree, giving the canopy a coarse texture. Their bark is deeply furrowed with scaly ridges that often curl outward. Catalpa trees have large, heart-shaped leaves arranged in whorls of three or opposite pairs. Their bark is ridged and scaly, and they produce white, bell-shaped flowers in late spring.
Redbud trees have heart-shaped leaves that emerge reddish and mature to green. They also produce abundant small, pink to purplish-pink flowers that bloom directly on branches and the trunk in early spring before leaves appear. The Redbud’s bark is smooth when young, becoming furrowed with age.
The Nature of Tree Pods and Their Contents
The “bean pods” on these trees are fruits, specifically a dry fruit known as a legume (characteristic of the pea family) or a capsule. Their role is to protect and disperse the tree’s seeds. As pods mature and dry, they split open to release seeds, which are then carried by wind, water, or animals.
Seeds vary in size, shape, and color depending on the tree species, reflecting adaptations for their specific dispersal mechanisms. While some seeds, like Kentucky Coffeetree seeds, were historically processed for beverages, many others, such as Black Locust and Honey Locust seeds, contain toxic compounds and are not suitable for human consumption. These seeds often provide a food source for wildlife.