Fig. 5.-General view of plots in root-knot control experiment, October 3,
 1940. Numbers refer to treatments. (Photo by Ray Robie.)

 3. Fallow-oats. Roots not removed; clean fallow, followed
by a cover crop of oats sowed during the second week in October.
 4. Sorghum-fallow. Roots not removed; cover crop of sor-
ghum, followed in November by fallow.
 5. Grass and weeds. Roots not removed; cover crop of native
vegetation, mostly grasses.
 Stalks on all plots were covered and left to decay in the soil.
In January all plots were fertilized with stable manure, about
8 tons per acre, then listed, and thereafter treated exactly alike
until the end of the tobacco crop season in July.

Fig. 6.-Method of listing the soil, leaving a balk in the center of the furrow.