942 
Journal of Agricultural Research vd. xxvn, No. 12 
The free larvae are incapable of traveling very far by their own move¬ 
ments. Haberlandt ( 11) claims to have secured infection in wheat 
plants growing 20 cm. from the point at which the galls were placed 
in the ground. Byars (6) states that he “found'abundant infection in 
wheat growing 30 cm. away from unopened galls.” Marcinowski (17) 
secured no infection in plants growing beyond 5 cm. from the buried 
galls. Appl (j) states that the larvae can not reach plants 10 cm. from 
the galls. 
The results ^bearing on this question, obtained by the writer during 
two seasons, were varied. Wheat was sown at Arlington Experiment 
Farm in the fall of 1919 in circular plats at different distances from the 
central area in which galls were placed 5 cm. below the surface of a sandy 
clay loam. A metal cylinder surrounded each plat to prevent washing. 
Wire cages were used to exclude birds and rodents, and every precau¬ 
tion was taken to prevent accidental spreading of the organisms. In¬ 
fection was not secured in any plants growing beyond 10 cm. (4 inches) 
from the infested area. * 
Table XIII .—Effect of placing galls at different distances from the seed on the degree of 
infection in the heads of Prelude and Marquis wheats , Madison, Wis., IQ22 
Distance galls were 
placed from seed. 
Heads of Prelude Wheat. 
Heads of Marquis Wheat. 
Exam¬ 
ined. 
Infected. 
Healthy 
Shat¬ 
tered.® 
Exam¬ 
ined. 
Infected. 
Healthy 
Shat¬ 
tered.® 
Inches. 
74 
Total. 
60 
Per 
cent. 
81 
5 
9 
218 
Total. 
65 
Per 
cent. 
30 
133 
20 
100 
72 
72 
20 
8 
210 
46 
22 
140 
14 
3 . 
130 
80 
62 
38 
12 
ISO 
26 
17 
zz6 
8 
140 
56 
40 
0 
84 
90 
12 
13 
77 
z 
6. 
170 
63 
37 
85 
22 
180 
16 
9 
160 
4 
IS® 
SO 
33 
90 
10 
107 
7 
7 
zoo 
O 
12. 
100 
30 
30 
65 
S 
I 4 S 
3 
2 
Z42 
O 
a Heads wholly or partly threshed by birds or by handling so that conclusive data could not be obtained. 
This experiment was later repeated at Madison, Wis., spring wheat 
being used in this case in a black garden soil. Frames 4 feet square 
were sunk into the ground several inches and allowed to project above 
the surface about 2 inches. Within each of these frames and 4 inches 
from it was another frame sunk inch into the ground and projecting 
]/2 inch above the surface. On April 15, 1922, the area between these 
two frames was heavily inoculated with galls, whole galls in half of the 
space and coarsely ground galls in the other half. On April 21 Prelude 
wheat, a very susceptible spring variety, and Marquis, a more resistant 
variety, were sown in the center of the different frames at distances of 
1, 2, 3, 4, 6, 9, and 12 inches from the infested outer area. A few ker¬ 
nels were sown in the inoculated soil to test the virulence of the inoculum. 
On May 15, about three weeks after sowing, abundant symptoms were 
observed in the Prelude plants 1 and 2 inches from the inoculated area, 
while all the plants growing in it were badly distorted. A few days 
later several plants 3 inches from the inoculum showed decided symp¬ 
toms and upon examination were found to contain swarms of larvae. 
On June 5, or 45 days after sowing, 12 badly infested Prelude plants were 
found, 4 each at 6, 9, and 12 inches, respectively, from the inoculated 
area. When ripe, the plants in each frame were harvested and each 
