North Central Forest Experiment Station, USDA Forest Service
Proceedings of aspen symposium '89; Duluth, MN.
General Technical Report No. NC-140
Log sorting is necessary when processing aspen saw-dry-rip (SDR) to select optimum log diameter and to minimize number of logs with dark-colored centers. Wetwood, which is difficult to dry, is commonly associated with these dark centers. SDR processing involves drying 7/4- to 8/4-thick live-sawn flitches. Drying the flitch and then sawing studs produces straighter studs than sawing first and drying in stud form. High-temperature kiln drying (230 o F to 240 o F) has given good results with several species (such as, basswood and yellow-poplar). For species likely to contain wetwood (aspen, cottonwood, willow), high-temperature drying is not recommended. A kiln schedule for aspen with maximum temperatures of 190 o F to 200 o F followed by equalizing at 12 percent EMC is suggested.
Boone, R.S. & Adams, R.D. 1990. Sorting aspen bolts and drying aspen flitches for SDR. Proceedings of aspen symposium '89; Duluth, MN. General Technical Report St. Paul, MN. US Department of Agriculture, Forest Service, North Central Forest Experiment Station. 259-299.