@Sleek
I'm still just getting started with bowmaking...  It hasn't been a year yet since I caught the bug, but I started to get the hang of tillering after about 9 bows.  A few abject failures along the way, but I'm up to 16 now, with a few shining moments.
I've had some success with a few Hickory flatbows, and churned out five 60-62" Osage Cherokee Hunting bows (simple D bows) that turned out nice.  Most of the Osage was gifted to me, but I've used most of it.  The Osage I found around my place had really tight growth rings, and was the source of some of the failures in my early attempts.
I recently cut several trees and stocked my basement with Elm, Ironwood (Hornbeam), Hophornbeam, Sycamore, Tree of Heaven, Hackberry and a beautiful 80' Hickory tree that'll yield 30+ staves.  I have one more big log to split. Most of the hickory is 6 1/2 or 7' long and split to about 4- 4 1/2", and pretty straight.  There's a little woodpecker damage to some of it, but most of the damage is deep enuf to work around and not be an issue.
The bows I had in mind to make are just regular Hickory Flatbows.  I want to keep practicing with that style for a bit to hone my skills and get better.  I'm not too keen on getting into recurved limbs just yet. I'm sure that'll get my attention soon enough, but I don't wanna get ahead of myself.  Still a rookie.
@Jim Davis
Thanks for the formula!  That should come in handy.
@Badger
I had lower 60's in the back of my mind, so thanks for that info...  I still have to physically check both people to verify their real draw length and not rely on a measurement from their chest to fingertips.  My own draw length is 1.5" shorter than that kind of measurement.