I too was wondering about Catalpa at one point and read everything that's been mentioned here. Not a good bow wood. However, I did turn up just ONE source that mentioned it being used occasionally in Yumi bows. I'm guessing maybe the Catalpa served as that side pieces that flank the laminated bamboo core of a Yumi. However, I couldn't find out anything else on that usage of Catalpa in Yumi bows so I passed up my chance to get a nice arrow-straight log of it.