Robinia pseudoacacia (Black locust)

Black locust is fast growing and native to the midwest and Eastern US. In the Fabaceae family, they fix nitrogen with bacteria in their roots, and this ability can change plant communities where this tree migrates to, such as coastal regions where soils are often nutrient poor. These are pioneer species, moving in to improve soils in disturbed areas, and yet also reproduce vegetatively with rhizomatous shoots and from seed. Black locust bark has shallow furrows that deepen with age, and their small 1-2 inch leaves are compound and alternate. Quail, turkey and otter birds eat black locust seeds. A very common street tree, urban children like me used the seed pods to play role-playing games.

They have been used for erosion control and land reclamation in old mining sites worldwide. The Cherokee used the bark as an emetic and crushed the roots for tooth ache. The genus Robinia derives from French gardener Jean Robin, who brought seeds from Louisiana to France in 1601. A significant amount of honey made in the US is from black locust flowers, and in Europe, honey from this tree is called ‘acacia honey’. Black locust hosts 67 different Lepidoptera, more than many native species where the tree colonizes. The wood is rot resistant due to lignans in the heartwood, and two fungus-killing flavonoids, and has been used for fencing and all outdoor exposed structures.

Elizabeth Oriel 2022