Black Locust Tree- Robinia pseudoacacia
In Europe the Black locust tree is considered to be highly prized as an urban street specimen, because it tolerates air pollution very well. The graceful white flower racemes that hang from the branches are extremely fragrant and perfume the air for shopping pedestrians.
The aromatic Back Locust flowers begin blooming in May and are considered edible and tasty like citrus flowers. Ironically, all other parts of the Black Locust tree are poisonous and should not be planted near livestock grazing sites. The lacy leaves are airy and constantly flutter in the slightest breeze. Leaflets can grow about eighteen in number and are attached to a midrib one foot in length. At night the leaves fold up as daylight fades, and likewise, the Black Locust tree leaves will contract during rain. In the Fall the deep green leaves that are silvery green underneath, turn bright yellow, and because of their tiny size do not need raking when fallen on the ground and then disappear in the grass as a fine mulch.
The Black Locust tree is a very fast growing tree that can produce a 4 foot trunk diameter and on old trees can reach 100 feet in height. This fast growing tree characteristic will rapidly enrich poor soils, because the Black Locust tree is a legume, so that nitrogen fixing bacteria grow into root nodules loaded with nitrogen organics. The Black Locust trees are very cold hardy, native American trees that range from the North Georgia mountains to Pennsylvania and then grow Westward to Oklahoma.
After flowering the Black Locust trees attract bees that produce a highly desirable, delicious, gourmet honey that is marketed nationally. After flowering the tree forms flat bean-like seed pods during the fall that can hang in the tree until spring. Tiny thorns are present at the base of the leaves of each Black Locust tree.
The dense wood of the Black Locust trees is very heavy and hard and contains organic flavonoids that preserve the wood in decorative, split- rail fences 100 years or more, even when in contact directly on top of the ground.
Farmers collect black locust tree trunks to use as fence posts in wet pastures, where most other woods would disintegrate in short order. Black Locust firewood is considered choice, because the heavy dense wood has a heavy heat content that produces very little smoke and the logs even burn when wet. The Black Locust tree can form a colony of small trees that grow from the base, and the tree when cut down will rapidly grow back in to another Black Locust tree that rises from the base of the mother tree.