44 CIRCULAR 639, U. S. DEPARTMENT OF AGRICULTURE 
tremely laborious, and rather poor applications frequently attend 
their use. A high, two-wheeled cart equipped with gasoline spray 
-pump and nozzle boom (fig. 50) has been found fairly satisfactory, 
F'rGure 48.—A portion of a cured tobacco leaf of the cigar-wrapper type, showing 
the typical ‘‘white veins” caused by the feeding of the tobacco thrips. Cigars 
wrapped with such leaves have an undesirable appearance. 
although it causes some damage when turning at the ends of the 
tobacco rows. As this type of sprayer straddles one row of tobacco, 
it cannot be used after the plants have been tied up to the top of the 
shade structure. Spraying after this time appears to be rather im- 
