Air Permeability and Creosote Retention of Douglas-Fir

Creosote retention and air permeability of sapwood, included sapwood, and normal heartwood of mountain-type Douglas-fir was correlated with specific gravity, growth rate, percent summerwood, tracheid length, number of longitudinal resin ducts, alcohol-benzene, acetone, and ether-soluble extractive contents of the corresponding zones. The effect of pressure and temperature on creosote retention was tested in sapwood, included sapwood, and normal heartwood. Test specimens were extracted in different solvents and the ease of penetration determined by creosote impregnation. Evidence is provided to support the conclusion that the presence of extraneous materials in the capillary structure of the included sapwood and true heartwood, e.g. in the openings of the pit membrane, is a critical factor prohibiting penetration.

You must be logged in to download any documents. Please login (login accounts are free) or learn how to Become a Member