Which wood species moves least with the seasons?

White pine moves the least of the fourteen species here across a dry winter to a humid summer; hickory moves almost twice as much. Full ranking, and why the sawing decision usually matters more than the species choice.

White pine moves the least of the fourteen species here — about 3/16" across a 12" flat-sawn board between 30% and 70% relative humidity.

Hickory moves the most, about 5/16" over the same board and the same humidity swing — 94% more movement from species choice alone.

How that is worked out

  1. Movement is width × a species coefficient × the swing in moisture content, and the coefficient is the only thing species changes — the arithmetic itself is identical for all fourteen.
  2. Run the same 12" flat-sawn board through the same 30–70% humidity swing for every species and only the coefficient moves: White pine at 0.00212 per 1% MC against Hickory at 0.00411.
  3. This ranks flat-sawn boards, the way most lumber is actually cut. Quarter-sawing any one of these species cuts its own movement by roughly half — a bigger lever than switching species, and the two stack.

Movement of a 12" board, 30–70% RH, least to most

Movement of a 12" board, 30–70% RH, least to most
SpeciesFlat sawnQuarter sawnFlat sawn, % of width
White pine3/16"1/16"1.4%
Cedar3/16"1/16"1.6%
Mahogany3/16"1/8"1.6%
Cherry3/16"1/8"1.7%
Douglas fir3/16"1/8"1.8%
Walnut1/4"1/8"1.9%
Ash1/4"1/8"1.9%
Sapele1/4"1/8"1.9%
Soft maple1/4"1/8"2.0%
Poplar1/4"1/8"2.0%
Hard maple5/16"1/8"2.4%
White oak5/16"1/8"2.5%
Red oak5/16"1/8"2.5%
Hickory5/16"3/16"2.8%

Worth knowing

  • These are Wood Handbook coefficients — measured properties that do not go stale, but do vary between trees. A species figure is a good bet across a stack of boards and no promise about the one in your hand.
  • The humidity swing is about the room, not the region. A heated house in a cold climate can be drier in January than a mild coastal climate ever gets, whatever the species on the floor.
  • This uses the tangential coefficient (flat sawn), which is the worse case and the common one. A species low on this list quarter-sawn can move less than a species high on it flat-sawn — the cut and the species both matter, and cut is usually the bigger lever.