Newsletter: Recovery in Western Juniper Solid Wood Products

 

 

by Scott Leavengood, OSU Extension Service
from the Western Juniper Newsletter, Vol. 1, No. 2, Summer 1996.

While I was in Eugene visiting wood product manufacturers recently, I showed one a 4 ft. juniper board. As you might suspect, one comment was: "I didn't think you could get that much out of a juniper!". My reply was probably similar to what many of you who have worked with juniper would have said: "It depends."

For example, it depends on what "quality" of logs we are talking about: Short and squat with lots of taper and numerous large limbs, or tall and straight with relatively few limbs. It also depends on the desired end product. For example, is it lumber, chips, finger-jointed/edge-glued panels, cut stock, or flooring?

Recovery data for western juniper vary greatly. Much of it was gathered in the course of in-service testing and market research, or informally during small production runs. Because of its importance to many interests though, an initial summary is offered below.

Rough-Cut, Mill-Run Green Lumber

Over 150,000 bd. ft. of rough-cut, mill-run lumber has been produced over the last four years.

  • On average, it takes about 3.5 to 5 tons of saw logs to produce one thousand board feet(MBF) of piece-count, tallied lumber (or approximately 230-310 bd. ft. per ton of logs).
  • Scribner Decimal C Eastside Log Scale overrun has varied from 167% to -73%. Butt swell, bark seams, dry rot, and different cutting specifications and expertise all contributed to this variation.
  • Saw log segments averaged 24-26 ft. in length, 14-18 in. in diameter (large end), and 800-1,100 lbs.
  • A certified grader was present on one run for green fencing - about one-third was graded #1, one-third #2 and one-third #3.

Variation in the amount of material needed to produce 1 MBF is due primarily to choice of logs, and processing equipment and expertise. A "good" juniper saw log:

  • Is a minimum of 24-26 ft. in length to a 4-6 in. top;
  • Has no twist; and
  • On its best face between 8 ft. and 18 ft., averages 12 in. or more between limbs, or if limbs are spaced less than 12 in. apart, average limb diameter is 1 in. or less.

(Note: See also the on-line Log Sort Criteria and Lumber Grade Rules)

Many stands have no sawlogs.

Finger-Joint Products

The first finger-joint trial of the Western Juniper Commercialization Project used left-over #2 fencing material, mainly to test gluing and finger-joint characteristics. No problems were encountered but recovery from lumber was only about 15%.

Four years later, average recovery for "rustic" finger-joint products from lumber (solid knots, no voids or bark seams) is probably closer to 40%. Further improvement in recovery is expected as markets are entered which accept more knotty material. Clear cuttings from mill run have averaged much higher than expected (40-50%).

Reports will be available in January 1997 with more detailed information. It is expected recovery figures will improve as target end-product is better identified and communication is improved between the logger, primary processor, and secondary processor.

For More Information: Scott Leavengood, OSU Extension Service (541) 883-7131

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