A. Corresponding editor Paul Fisette responds: The heartwood (but not the sapwood) of both red and white cedar is naturally decay resistant. Although the two species are listed in most handbooks as having heartwood with comparable rot resistance, the experience of many carpenters suggests that red cedar is a little more rot resistant.
Several factors may account for this. When grading white cedar, it is quite difficult to distinguish between heartwood and sapwood, so it is likely that at least some sapwood slips into the all-heart grades.
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