Fusarium Blight of the Soy Bean 
31 
teristics but grading in texture from stone and gravel on the 
one hand, thru sand and loams, to a heavy clay on the other.” 
(30, p. 19.) 
In Xorth Carolina, Fusarium traelieiphilum occurs mostly 
in the Coastal Plains or eastern one-third of the slate and in this 
section the Xorfolk soils series is the most important one, not 
only because of its percentage of area but also because of its 
agricultural value. These soils are characterized by the light 
gTay to grayish-yelloAv color of the surface soils and by the yel- 
low color and friable structure of the subsoils. They occupy 
nearly level to rolling uplands thruout the Atlantic and Gulf 
Coastal Plains, and have been derived mainly from Piedmont and 
Appalachian material. 
The writer has observed so}^ bean blight in the field on sand, 
fine sand, sandy loam, and fine sandy loam soils, but not on those 
with a higher percentage of the finer particles such as silt, silt 
loam, clay loam, or claju^ Inoculations in the greenhouse thru 
mixed soils to which a large amount of coarse sand had been 
added also resulted in a higher percentage of infection. lYollen- 
weber (31, p. 46) concluded, from observations made during his 
inoculation experiments, that light sandy soils^ favored the de- 
velopment of Fusarium spp. inhabiting the soil and causing wilt 
diseases. 
An experiment was conducted in which soy beans were grown 
in eleven types of soil of the Xorfolk series which were collected 
with considerable care from typical localities in the Coastal 
Plains with the assistance of Mr. C. C. Logan of the Xorth 
Carolina Station who has had considerable experience in making 
soil surveys. That there are no well-defined limits to indiAudual 
types, and that different survey parties often disagree in classifi- 
cation and limits of areas, was kept constantly in mind. Conse- 
quently soil maps were used only to assist in the general location 
of several examples of a type from which an average could be 
selected. Furthermore, as nearly as it was possible, soils were 
selected which contained a normal amount of humus for the type 
and to which fertilizers had not been added since the previous 
crop had been harvested but to which they had been added in 
the form of complete commercial fertilizers for the benefit of tliat 
crop. So far as known neither soy beans nor cowpeas had e^'er 
been grown on these soils. 
Each type was obtained in quantities of 600 pounds. Two 
hundred pounds of the first six inches (surface), 200 of the second 
^The soil referred to previously by the writer (6, p. 424) as a clay was instead Cecil 
sandy loam. 
-By this term it is supposed that he referred to soils with a larger percentage of 
coarse than of fine particles. 
