Drying Loads with Mixed Moisture Content

It's a balancing act you have to watch out for the drier wood causing the wetter wood to dry too fast and check. October 4, 2011

I have different stacks of different species from which I've been sawing from time to time. When I come to load the kiln with the same species and with the same thickness (white oak ),the mc varies from the lumber I sawed 3-6 months apart. Am I going to have a problem while its drying in the kiln?

Forum Responses
(Sawing and Drying Forum)
From Gene Wengert, forum technical advisor:
The settings in the kiln will likely be a compromise if the incoming MC varies by more than 10% to 15% MC. Especially critical for oak to have fairly uniform MC.

From contributor A:
I try not to put green in with air dried but if I have several piles of oak and they differ by a few months of air drying I put them in and dry by the highest MC. The thing you have to watch is the drier wood will soak up some of the wetter woods moisture and cause it to check by drying to fast.

From Gene Wengert, forum technical advisor:
You also must be extremely careful not to let the dry surface pick up moisture, as this will case the surface to swell and drive small surface checks deeper.