June, 1955 
of three sides of each mat from the edge 
of the central pad to the periphery of my- 
celial growth. Each group of three disks 
was placed in a 10-ml. water blank and 
thoroughly crushed and shaken. ‘The 
number of conidia in | ml. of suspension 
was then estimated, and the spores were 
germinated on water agar. The average 
number and per cent of germination of 
spores from each three-disk sampling were 
compared with the number and per cent 
of germination of conidia from other 
three-disk samplings on the same mat. 
The approximate number of spores 
found on the four mats ranged on differ- 
ent mats from 280,000 to 1,300,000 in 
ea 
’ a e° af ma 
; 
Curt: Oak Witt INoOcULA 
289 
1 ml. of suspension, and the germination 
rate ranged from 13 to 41 per cent. In no 
case was the difference in the average 
number of spores between any two sam- 
plings of the same mat greater than 40,- 
000, and the difference in germination 
rate did not exceed 5 per cent. It seems 
unlikely that such differences would be 
significant. ‘Therefore, it is believed that 
representative samples were obtained by 
the method employed in these studies. 
Transporting Samples 
As it was necessary to store collected 
samples of the fungus at low tempera- 
Fig. 7—Mycelial mat of Endoconidiophora fagacearum grown on sterile oak wood in 
wheat bran broth. 
