The Effect Of Stem Girdling On Wood Quality

Adam Taylor, Paul Cooper

Abstract


Mature trees of three species—tamarack (Larix laricina) (n = 2), soft maple (Acer rubrum) (n = 4), and red pine (Pinus resinosa) (n = 5)—were phloem-girdled one to two years before felling to test the folk wisdom that girdling produces wood with improved properties. The wood from these trees was compared with wood taken from ungirdled control trees felled at the same time. Sapwood and heartwood, from control trees and from above and below the girdle of treated trees, were examined for parenchyma viability, moisture content, various extractive components, and susceptibility to sapstain and mold fungi.

Parenchyma viability was reduced in girdled trees below the girdles. Moisture content was reduced in the conifers, especially below the girdle (> 50% reduction vs. controls), but not in maple. Girdling changed the extractives concentration in the sapwood, although in different ways for the different species. Soluble polysaccharides were reduced in the girdled tamarack trees above and below the girdle, but increased in concentration above the girdle in the pine and maple. Starch was depleted from the girdled tamarack and pine, and below the girdle in treated maple trees. Phenol-type extractives were higher below the girdle in maple.

In general, susceptibility to sapstain and mold fungi was reduced on wood from girdled trees. This effect was most evident below the girdle and in pine trees.


Keywords


Girdling;wood quality;heartwood;extractives;sapstain;mold

Full Text:

PDF

Refbacks

  • There are currently no refbacks.