Catalpas

For Throwback Thursday, here's a tree that is both easy and difficult to identify, a catalpa tree. The large leaves and fruit that resembles an unusually long string bean make catalpas pretty distinctive. On the other hand, it's pretty difficult to distinguish the Northern Catalpa and the Southern Catalpa, where the Northern has larger flowers but fewer of them and has a slightly broader seed pod [1] [2].

The catalpas aren't native to NJ, with the Northern Catalpa originating around the Arkansas/Missouri/Illinois shores of the Mississippi, and with the Southern Catalpa coming from central Alabama/Mississippi.

They are a host plant for the Catalpa Sphinx moth; as caterpillars they can defoliate a catalpa tree (though the leaves usually regrow). Although there are catalpa trees around here, I don't know if we've got enough of them to support much of a population of these moths [3].

Despite reminding us of string beans, are (unlike some trees) not legumes. (If you break the fruits open, you won't see anything like the relatively large individual beans/peas in a legume pod.)

October 12, 2017 at Murray Hill
Photo 11385358, (c) jpviolette, some rights reserved (CC BY-NC)

October 12, 2017 at Murray Hill
Photo 11385361, (c) jpviolette, some rights reserved (CC BY-NC)

[1] Since most of the time I don't see their flowers, we're left with slightly broader seed pods to distinguish them, a pretty subjective field mark.

[2] Since there are reports of these catalpa trees hybridizing with Asian catalpas, I'm almost certain they can hybridize with 1 another, making identification (especially outside their native ranges) even more problematic.

[3] Catalpa Sphinxes can survive in NJ though, since they're found as far north as Maine.