by Professor Gene Wengert
Q.
How should butternut burls be dried?
A.
For drying butternut burls, treat them almost the same as lumber, except do several things to keep them flat--use stickers about every 12 inches; use weight on the top of the stack (maybe 100 pounds per square foot--a couple of concrete parking lot bumpers?); and dry them with plenty of air flow in a dry location. (Fast drying is preferred as this creates dry fibers on the outside of the piece--these dry fibers are nearly twice as strong as wet fibers, so they can more easily resist the tendency to warp.)
There is also a suggestion for other species (butternut dries easily, but many other species are hard to dry) in DRYING EASTERN HARDWOOD LUMBER, U.S. Dept of Agr. Handbook No. 528 (out of print--available in most large libraries, or in small libraries via interlibrary loan).
Professor Gene Wengert is Extension Specialist in Wood Processing at the Department of Forestry, University of Wisconsin-Madison.
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