| Abstract: | - Equilibrium in the moisture content of the stem appears to bereached at a given percentage of saturation rather than at apercentage based on the dry weight, and this method of expressingmoisture content eliminates many of the fluctuations apparentwith the latter.
- Summer moisture content in Sitka spruce (Piceasitcbensis, Carr.)was highest on the site with the highestrainfall and lowestwith the lowest rainfall. It decreased inlate summer, suddenlyin Sitka spruce (in August) and graduallyin Douglas fir (Pseudotsugataxifolia Brit.).
- There was asharp moisture gradient from cambium to heartwood,the saturatedzone being very narrow except on the wet Sitkaspruce site.In the Douglas fir it appeared that water couldbe withdrawnfrom the layers just behind the transpiration streamfasterthan it could be replaced, leaving this zone drier thanthesurrounding layers.
- Lateral root pruning in Douglas fir ledto the drying out ofa narrow strip of tissue in the stem.
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