Measuring Standing Trees and Scaling Cut Timber

Timber Sale Volumes, Weights and Prices

by Julian R. Beckwith, III
Associate Professor
(Wood Products)
D.B. Warnell School of Forest Resources
UGA Cooperative Extension Service

November 1997

Timber is Georgia's number one single cash crop for landowners. However, buying or selling timber can be a puzzling process, since different units of measure may be used for different products.

Larger timber has often been measured in ``thousand board feet'' (MBF), one board foot being equivalent to a 1$\times$12, one foot long. However, for a product such as sawtimber, different timber-measuring standards, called log rules, can be and are used to express timber volume (see next page). Certain log rules describe some timber types and sizes better than others. Traditionally, the Scribner log rule has been used for determining volume of pine sawtimber and pine peeler-logs, while the Doyle log rule has been used for hardwood sawtimber. Chip-N-Saw and pulpwood timber has usually been measured in cords, which equals a stack of wood occupying a volume of 128 cubic feet. In some cases it is not hard to be convinced that different units are used merely to confuse, in order to ``get a better deal.'' This might be true if unscrupulous timber buyers are trying to deceive landowners about value of their timber.



Figure 1: a single board foot.




Figure 2: a standard cord.


In order to simplify and to speed the process of determining amount of timber being bought, ``weight scaling'' has been adopted by most mills. This process involves weighing log trucks before and after unloading to determine the weight of logs brought in. For each mill, the price paid per unit weight (such as $/ton) is determined by relating log weights to average amount of finished product produced per unit log weight (such as MBF/ton). Many companies use standard weight-scale factors for pricing, but some perform detailed statistical studies of timber they buy, for their particular product or product mix. Weight-scale factors vary with log size, very large logs usually yielding higher product volumes per unit weight than very small logs. Thus, when timber varies greatly in diameter and height, different weight-scale factors must be applied to best relate log weight to expected product volumes. Timber quality, wood density and average moisture content, as well as the efficiency with which a particular mill can produce a final product, also influence the weight-scale factor used and the price paid at a mill.

Buying/selling by weight also encourages landowners and timber harvesters to get timber to a mill quickly, before it loses moisture and thus weight. Mills purchasing timber benefit from fresher, although heavier, logs too, because they contain less stain and decay, and fewer wood destroying insects.

Furthermore, weight scaling favors good timber management, by encouraging timberland owners to sell dead and/or diseased trees quickly while the raw material quality is still good, and their moisture content and weight are still high.

Georgia law does not require specific units of measure for timber sales. Department of Agriculture regulations do require that, in general, firewood be sold by the standard cord or fraction of a cord. However, in order to help assure honesty and fairness when buying or selling timber by weight, Georgia law does specify how price may be stated. The unit of measure for weight-based sales must be pounds or tons. Even if a buyer uses weight to determine volume of timber being bought, the seller or potential seller must be provided a quotation in dollars per 1000 pounds. Such quotes allow easier comparisons among multiple offers.

The process of selling timber can be traumatic for both buyer and seller, but weight scaling may make it a little more understandable and easier to deal with.


Some approximate conversion factors for price quotes based on different log rules:


  • To convert sawtimber prices from Doyle to Scribner, multiply Doyle prices by .75
  • To convert sawtimber prices from Scribner to Doyle, multiply Scribner prices by 1.33
  • To convert sawtimber prices from Doyle to International, multiply Doyle prices by .62
  • To convert sawtimber prices from International to Doyle, multiply International prices by 1.6
  • To convert sawtimber prices from Scribner to International, multiply Scripner prices by .83
  • To convert sawtimber prices from International to Scribner, multiply International prices by 1.2

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