Well, that sapwood is just not as strong as heartwood.
one irony- Osage heartwood is probably one of the best bow woods in the world, but the sapwood is one of the worst.
Same with Yew, but the sapwood is useful... as a (carppy) backing.
-Squirrel.
BL is a good wood. I use sooo much of it. I use mostly 4-6 inch diam logs... the sapwood is very thin, the rings in general are thin, and the stuff is very strong.
No big stuff near my house
Use a big tool(hatchet is great) to split off the sapwood, and make arrows from it. make a bow from heartwood and arrows from heartwood chunks left over.
It is pretty cool if you make a bow and arrows from the same tree, with the bark making a quiver.
BL is very strong stuff, but it cannot take much compression, be careful.
Sapwood is not nearly as tough. However, it makes good arrows.
Sorry for ramblin!