FUNGI AS CONTRIBUTORY CAUSES OF WINDFALL 



707 



tions, cutting operations, etc., were recorded as secondary causes of 

 windfall. Of the number of areas having fungi as secondary causes 

 of windfall, 2 are reported without having given the loss in feet board 

 measure or the valuation. Five of the areas having other secondary 

 causes than fungi are also similarly reported. 



Table 2. — Table Shozving the Grouping of the Various Windfall Areas of 

 Table i under the Principal Secondary Causes of Windfall 



Table 2 gives the relative importance of the various secondary 

 causes of windfall as found in the areas reported in Table i. It is seen 

 that windfall due to cutting operations and to soil conditions rank first, 

 followed by fungi, exposure, and so on dow^n. It is significant that 

 fungous activity is shown to be a close second as a secondary cause of 

 windfall, and that cutting operations and soil conditions are first. In 

 District I, 30 per cent of the windfall areas were reported with soil 

 conditions as secondary cause, 14 per cent equally to cutting operations 

 and fungi, and 10 per cent to exposure. In District 2, 31 per cent to 

 cutting operations, 17 per cent equally to soil conditions and to expo- 

 sure, and 14 per cent traced to fungi. In District 6, 27 per cent were 

 reported with fungi as secondary causes, 23 per cent equally to cutting 

 operations and to soil conditions, and 11.5 per cent to exposure. 



Cutting operations resulting in the removal of a portion of the stand 

 and suddenly exposing a previously protected portion are evident sec- 

 ondary causes in the overthrow of trees. It is to be expected that too 

 severe marking, or marking without considering the wind-resisting 

 powers of the remaining stand, will invariably result in windthrow on 

 such sites exposed to severe wind action. On the other hand, little 

 attention has been paid to the part played by fungi in rotting, and tiuis 

 weakening the roots and trunks of trees to such an extent as to cause 

 wind l)rcakag('. I 'or the reason that fungi have been found to cause a 



