The progress of the transformation is somewhat influenced by the rate of growth; it is slower
in slow growing trees and usually also on the slower-growing radius, i. e., there are more rings of
sapwood. The width of the sapwood, on the other hand, stands in relation to the rate of growth
in an opposite manner; it is wider in young and thrifty than in old and stunted trees, and widest
along the greatest radius of any se<jtion; similarly, it is wider in the faster- growing loblolly, Cuban,
and spruce pines than in the slow-growing longleaf.
Besides being of a lighter color the sapwood differs from the heartwood in several respects.
