Awesome, thanks so much for all that info. I'm glad to finally know for sure what it is. I like the arrow idea - I could definitely use more arrows, and have been looking for something that would serve well for some shafts. I don't have a lathe, but I do have a variable-speed corded drill, which, with a little rig building, I'm told can make a pretty good poor-man's lathe. I might give that a shot.
Speaking of arrows - I have started collecting reeds for making them. I'll post that in another topic with some pics.
Although, just for fun, I might save a four foot section of it and turn it into a bow anyway. Just to see what happens. I'm almost taking the "not a bow wood" advice as a challenge now.
Of course, if "not a bow wood" ever means "it will blow up in your face", I may take the advice rather than play with fire. I don't want to use a wood that is incredibly brittle or so soft that it won't hold a tiller.