How Good Is Catalpa Firewood? Axe Adviser While catalpa trees are not generally considered highly toxic, some parts of the tree, particularly the roots, are known to be poisonous according to the USDA Plants Database. The leaves and seed pods A Pruning Guide for the Catalpa: When, Why & How? MOOWY Southern Catalpa (Catalpa bignonioides): Essential Guide Catalpa Tree Branches Pods Leaves Stock Photo 2586961485 Shutterstock Polk Salad Annie