I can't do quotes, but I had a Manny Guava bow That came to me with 4 fretts and everytime I pulled it , another one would pop up. It's in my garden right now. I had another one that Ryan O' gave me at the Classic one year that is holding up one of my pineapples.
But, the toughest piece of wood I've ever seen is Casarina, Australian Pine. Parnell brought a little bow up to my house one weekend and I tried to break it. it did around 35" and 50#. We left it leaning against the shelf with the top limb folded over, didn't break, just collapsed. We ate lunch , came back out about an hour later and it had recovered to
, almost it's previous form. But still broke. Hell'aseous, interlocking fibre in that wood.