Ah, the Locusts. Those trees that are called Locust, at least in Indiana, are contained within two genera in the Fabaceae family – the legumes. Yeah, right there with the beans and the clovers.
The two Gleditsia Locusts are Honeylocust and Water Locust. The three Robinia Locusts are Black Locust, Clammy Locust and Bristly Locust.
The Bristly Locust is native to southern Indiana, but can be found in northern Indiana associated with old homesteads, similar to Black Locust. Clammy Locust is found in the very northwest corner of the state.
Bristly locust is a short tree/medium shrub. It is quite showy, both flowers and foliage, which is why it was planted around homes. You don’t see much of it anymore … I don’t know why. There is a small patch of it down the road from me. I’ve never seen it set fruit yet, although there are always a lot of blossoms.