§42 JOURNAL OF FORESTRY 



people who inhabit regions subject to seismic disturbance. Cutting the 

 forest clean by small areas or cutting it very lightly by large areas 

 will not obviate or lessen the calamity when it comes, for in any 

 forestal system there always will be standing trees to be blown down. 



One distinctive feature in the distribution of the damage of this 

 vear's storm may be interpreted as indicating a possible local variation 

 in treatment. On Cherry Creek and Fourmile Creek occurred in 

 each case an exceedingly heavy volume of windfalls concentrated in 

 a small area near their mouths, or rather at the ends of their valleys. 

 This volume is believed to have been caused by the funneling of the 

 wind currents which had entered the wide basins of the upper valleys 

 and debouched through the comparatively narrow channels of the valley 

 ends. The valleys lie east and west, and the wind was from the west. 

 Restriction of the course of the wind by the local topography in this 

 way, of course, greatly increases its intensity. Mr. Wells pointed this 

 out and cited the example of the intense winds through the Columbia 

 Gorge in the vicinity of Bonneville at times when farther up and 

 down river there are only moderate wind velocities. If such areas — ■ 

 which might be considered areas of wind, drainage — should be found 

 by later experience to be regularly susceptible to winds of this nature, 

 the natural conclusion woul,d be to clear cut locally. While this would 

 not lessen the damiage in the case of a catastrophic storm, it would 

 entirely obviate it in the case of the less severe storms which may 

 occur every four or five years and which always throw down trees 

 whose wind resistance has been weakened by the liberation of heavy 

 selection cutting. 



While this investigation into the causes and effects of windfall and 

 the remedies for the problem on the Crater National Forest has pro- 

 duced some tangible facts, insofar as the unusual storm of April, 1920, 

 is concerned, there is still much to be learned about the less destructive 

 storms — though more menacing ones to our silvicultural practice — - 

 which apparently are apt to recur every few years. It is known from 

 our very intensive windfall study on the Whitman Forest in 1914, 

 from windfall history studies on old private cuttings, and from much 

 observation of the results of five destructive wind storms in the timber- 

 sale cuttings of the Crater and Whitman Forests, that no quality of 

 the tree itself or its site is sufficiently strong to resist the force of 

 these storms after the stand has been opened up by selection cutting. 

 It has been learned that these storms blow down the trees in any 



