THE ROTS OF WESTEEH WHITE PIKE. 21 



age, then it follows that the production of sporopliores will also in- 

 crease as the decay develops to that stage where fruiting bodies 

 are produced. It is also to be expected that when the period of 

 maximum sporophore production is passed there will be a gradual 

 decline in the numbers produced and also in the numbers retained 

 upon the trunk. Fewer new sporophores are produced in the old- 

 aged trees of the stand, and of the old sporophores already on the 

 tree many die, become loosened from the trunk, and drop off. The 

 data show for both types of site that there is an increase in the 

 number of trees bearing sporophores and in the average number of 

 sporophores per tree, from the 61 to 80 to the 121 to 160 age classes, 

 inclusive, while a decrease is noted for the 161 to 200 and the 201 

 age classes. This indicates a maximmn sporophore production in 

 the 121 to 160 age class and a declining production for the age 

 classes following. 



Figures have been given which show that site plays an important 

 part in the development of rot in a stand. The consensus of opinion 

 among practical loggers is that low, flat, and poorly drained sites 

 bear stands having the greatest amount of rot and that the sites 

 where trees are freest from rot or where the rot percentage is small 

 are well-drained slopes or benches. The comparison of slope and 

 bottom sites in respect to rot percentage, both for age classes and 

 for the total stand, indicates that a greater amount of rot is preva- 

 lent on the bottom sites. A comparison between trees taken from 

 similar sites upon widely separated areas and having a difference 

 in average age of 10 years shows a difference of 1 per cent in rot be- 

 tween these two areas. The percentage is greater on the area having 

 the greater average age. The same indication is given by the figures 

 for the percentage of infected trees. These data also furnish evi- 

 dence of the influence of age upon the amount of rot to be found 

 in a stand. Further comparisons of trees occurring on slope and 

 bottom sites on the same sale areas also indicate that the trees on 

 the bottom sites bear a greater percentage of rot than those on the 

 slopes. 



In respect to the influence of site upon degree of injury the data 

 do not show conclusively that a greater degree of injury exists upon 

 bottom sites. The bottom sites with 2.4 and the slope sites with 1.9 

 (Table V) leave too small a difference to attribute them to the in- 

 fluence of site. Apparently greater percentages of infections are 

 traced to branch stubs on the bottom sites than on the slopes. This 

 may be due to the formation of a larger number of dead branches 

 on the bottom sites as a result of greater shade. Light more easily 

 reaches the lower branches of trees growing on a slope than of trees 

 growing on the bottom sites, providing the densities are about equal. 

 This might be a possible explanation of the formation of a greater 



