The Transatlantic bow made back in 2013 for a friend of mine has popped a splinter on the back.
It's a North American Yew heartwood belly with an English Yew sapwood back.
The splinter starts at a row of pin knots and runs about 6" down the bow. It doesn't go right through the sapwood. I'm not quite sure how I'll fix it, do I let in a a narrow strip or take the sapwood down to about half thickness right across the bow? I think it's about 75# draw weigh at 32" but I'm not sure, I'll re test it once it's repaired. Letting in a narrow strip is tricky and maybe a patch overlaying that whole row of pins would be good. I'll think on it over a nice cup of tea.
You can see from the pics, the sapwood back was very good and pristine, it still has some cambium on it, but the row of pins was obviously a weak point. Just goes to show how critical a bow's back is.
I like to keep an eye on bows and maintain them.
I have plenty of good Yew sapwood, as I keep all the strips I saw off when I have to reduce extra thick sapwood.
Meanwhile I'm making a 24" bow from one of the limbs of the rawhide backed primitive just for a laugh!