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to one side until it reached beyond the manure when it again took a 
downward direction until it reached the depth of 24 inches, Fine 
fibrous roots extended from the tap root into the manure, completely 
filling it with a mass of very fine white rootlets. None of the large 
roots extended into the manure. ‘The laterals were mostly about 6 
inches below the surface, with numerous fibrous roots reaching to the 
depth of 12 inches from the surface. Many laterals extended a dis- 
tance of 28 inches from the plant. : 
Row No. 2. The tap root extended nearly perpendicularly to the 
depth of 18 inches, when it became too delicate to trace. The larger 
roots were smaller than those of Row No. 1, but were more numer- 
ous, many extending 48 inches horizontally. The fibrous roots were 
larger and not so numerous, nearly filling the soil to the depth of 12 
inches. ‘The roots extended horizontally as far as the vines reached. 
From this it appears that the fibrous roots having an abundance 
of plant food near by, were more concentrated. Those in Row No. 
x extended to a greater distance in search of food. The tap root 
did not extend deeply into the soil in search of food. Its function 
perhaps was to supply moisture to dissolve the plant food contained 
in the manure and render it available. This question can, however, 
only be answered by further experiment. 
T'wo rows each of White Star potatoes, Top Over corn and Long 
Red Mangel Wurtzel were planted May 23 for the purpose of noting 
the effect of root pruning upon the growth of the roots. The roots 
were pruned July 16 by placing a six inch board alongside of the 
row close to the plants and cutting to the depth of twelve inches 
with a spade along the outer edge of the board. 
Aug. 4. Wurre Star Poraro, root pruned. Small fibrous roots 
had started where the roots had been cut off. The majority of the 
roots occupied the soil between two to eight inches deep. A few 
roots extended to the depth of 19 inches. Horizontally, roots were 
traced a distance of 30 inches from the plant. 
Wuite Star Porato, not root pruned. The roots extended about 
the same distances each way as in the former. There were more un- 
derground stems, the tubers were more numerous but smaller. ‘There 
were seven tubers on this plant, and only two on the former. The 
two tubers were nearly equal in bulk to the seven. 
Oct. 19. Wurre Star Poraro, not root pruned. Roots extended 
to the depth of 17 inches. Laterals extended 26 inches on each side 
of the plant. Most of the roots were within 14 inches of the surface. 
WHITE Star PotaTo, root pruned. The roots extended laterally 
only about 12inches. The majority of the roots were within 18 inches 
of the surface, numerous roots extended to the depth of 33 inches. 
Top OvER Corn, Row No. 1, July 3. The soil on each side of 
the row was thoroughly pulverized to the depth of 12 inches. Row 
No. 2 was cultivated with the hand hoe sufficiently to keep down 
the weeds. 
July 16, Row No. 1. The majority of the roots filled the soil to 
the depth of 9 inches. A few reached the depth of 16 inches. The 
soil on each side of the plant was filled with fibrous roots for a dis- 
tance of 12 inches, many of them extending a distance of 3 feet from 
the plant. 
