\ 
42 REPORT OF DEPARTMENT OF BACTERIOLOGY OF THE 
The results from the seed-inoculated plats are identical with those 
from the corresponding check plats except in two intsances, those 
of Nevins Bros. and R. A» Husted. The experiment of Nevins 
Bros. was not seen by a Station representative, but from the re- 
ports furnished it would seem that the seed-inoculated plats were 
better than the check plats and were good enough to be considered 
a success. The experiment with Mr. Husted was personally in- 
spected and the seed-inoculated plat was distingtly better than 
the check plat. | 
Aside from these two experiments there is no evidence from 
our experiments that carefully inoculated seed carried enough liv- 
ing Ps. radicicola to be of any use upon the fields; and an examina- 
tion of the plats showed few if any indications of an improve- 
ment resulting from a treatment of the seed with pure cultures of 
Ps. radicicola. The unfavorable result from this method of inocu- 
lation was as unexpected as it was unfortunate. The explanation 
of this rapid disappearance of the germs placed upon the seed has 
been given by Kellerman and Beckwith,?® who pointed out that 
the high osmotic pressures developed in evaporating the solution 
in which the bacteria were grown is quickly fatal to the germs them- 
selves. 
As will be seen from the results from inoculation by means of 
soil, 15 of these farmers had plats inoculated in this manner ad- 
joining the seed-inoculated plats and in ‘all cases except that of 
Mr. Robbins the soil-inoculated plats were a success. Not only 
was a failure transformed into a success by the inoculating soil 
in a number of cases but even on succcessful fields where the 
amount of inoculation naturally present was not up to the full re- 
quirement of the alfalfa, the growth of this plant was noticeably 
stimulated by the application of soil. On the contrary the benefit 
derived from the treatment of the seed with pure cultures of Ps. 
radicicola was so slight in comparison with the good results ob- 
tained from the use of soil that the inoculation of the seed was 
not continued after the season of 1905. 
* Kellerman, Karl F., & Beckwith, T. D. Effect of drying upon legume 
bacteria. Science, N. S., 23: 471-472. 1906. 
Applying soil from an old alfalfa field While very satisfac- 
tory results from this form of inoculation have been reported by 
experiment stations and by individuals, the tests by stations have 
not been planned with the idea of determining the percentage of 
success due to its use, and the private tests have generally been 
