swell-butted

If the old trees are few to the acre, the sprout clusters will be so far apart that excess of side light will produce clumps of swell-butted, short limby trees, of little use for lumber; that is, unless there is also a seedling growth of fir or other species to fill the blanks and bring up the density.

Practical Forestry in the Pacific Northwest Protecting Existing Forests and Growing New Ones, from the Standpoint of the Public and That of the Lumberman, with an Outline of Technical Methods Edward Tyson Allen