14 



James Stewart Wiant 



believed that the seedlings selected were typical in all respects of the large 

 numbers which were destroyed during the epiphytotic of that season. 



During the following season, collections were made from June 4 to June 

 23. As noted in table 1, the average loss from damping-off was low in the 

 regular nursery seedbeds of that year, so that while many seedlings were 

 collected from those beds the majority were taken from the experimental 

 beds where the incidence of the disease was very high. 



In addition to the seedlings collected at Keene during the season of 

 1927, specimens were at the same time received from a number of other 

 nurseries as follows: white and red pine from Gerrish, New Hampshire; 

 red pine from Milton, Pennsylvania; austrian and scotch pine from Am- 

 herst, Massachusetts; austrian pine, and Colorado, engelmann, and norway 

 spruce, from Framingham, Massachusetts; norway spruce from Essex 

 Junction, Vermont; and Japanese larch, norway spruce, and red, white, and 

 scotch pine, from St. Williams, Ontario. These were collected from June 

 11 to June 21, and were for the most part in good condition when received. 

 Isolations were made within a few days from the "time when the seedlings 

 were collected. While comparatively small numbers of the seedlings were 

 examined in each case, the results give some indication of the organisms 

 associated with the disease at these nurseries. A summary of these results, 

 together with those from the Keene nursery in 1926 and 1927, is given in 

 table 3. 



TABLE 3. Summary of Isolations from the Keene and Other Nurseries 



The results from the Keene nursery are very striking, in that 

 Rhizoctonia was isolated from the vast majority of more than a thousand 

 seedlings. Although particular care was used in searching for Pythium, 

 Fusarium, Alternaria, and other fungi which were found associated with 

 the diseased seedlings at the Ithaca nursery, these organisms were rarely 

 found at the Keene nursery in seedlings which were examined soon after 

 they exhibited the first symptoms of the disease. Direct microscopic 

 examination of such plants showed the tissues to be filled with the character- 

 istic mycelium of Rhizoctonia. A number of the fungi noted above were 



