Bark 2 web December 9, 2022 No Comments Share Share on Facebook Share on Twitter Pinterest Email Stem cross-section of a paper birch, showing the outer bark, phloem, cambium, xylem/sapwood and heartwood. Can you see the annual growth rings? Photo by Josh Shields. 0 Write A Comment Cancel Reply Save my name, email, and website in this browser for the next time I comment. Δ