TABLE 4.--Acreage corn treated for weed control in United States? 
Year Northeast North Central Total 
1,000 acres 1,000 acres 1,000 acres 1,000 acres 1,000 acres 
1949 386 4,173 --- --- 4,559 
1952 S44 7,276 865 165 8,150 
1959° 566 13, 384 1,666 104 15,720 
+ Estimates for 1949 and 1952 from U. S. Department of Agriculture, Statistical Bulletin 
156, April 1955; 1959 estimates from unpublished survey data accumulated by the Federal 
Extension Service, Farm Economics and Crops Research Divisions, Agricultural Research 
Service, U. S. Department of Agriculture. 
2 Estimates for Alaska, California, Delaware, Hawaii, New Jersey, New York, Ohio, 
Oklahoma, and Washington not included. 
TABLE 5.--Estimated cotton acres treated with defoliants and desiccants? 
i era a 
1,000 acres 1,000 acres 1,000 acres 
1940 trace 0) trace 
1946 250 0) 250 
1952 2,59 120 Pon 
1955 2,499 440 2,943 
1958 35,103 Io95 4,698 
1960 Shei (o\0) 2,500 6,250 
1 Estimates kindly furnished by W. H. Tharp, Cotton and Cordage Fibers Research Branch, 
Crops Research Division, Agricultural Research Service, U. S. Department of Agriculture. 
Significant progress was made during the past 5 years in the development of chem- 
ical methods for controlling soil-inhabiting plant parasitic nematodes on living plants, 
principally orchard and grove trees, but also in vineyards and nurseries. In studies in 
Arizona the treatment of the soil by introductionof 1,2-dibromo-3-chloropropane (DBCP) 
in the irrigation water has controlled the citrus nematode in heavily infested orchards and 
improved the economic returns as much as $90 per acre. 
Another advance in the last 10 years was the wide adoption of methyl bromide as a 
treatment for the control of nematodes, soil insects, fungi, and weed seeds in seedbeds. 
Other potential economic gains from the use of nematocides are illustrated by ex- 
perimental results obtained in Georgia. The yields of sweet corn, cotton, squash, okra, 
beans, and cantaloupes were increased 15, 25, 85, 300, 125, and 70 percent, respectively, 
by nematocidal treatments. 
Fungicides--Progress in the discovery and development of fungicides is shown by 
the following examples of fungicide usage to alleviate major disease problems. 
Effective, low-cost protectant fungicides are available for seedtreatment. Investment 
of a few cents per acre in these fungicides permits establishment of good stands of 
vigorous, disease-free seedlings of such plants as cotton, corn, small grains, peanuts, 
potatoes, sorghum, and vegetables (5). The investment of 30 cents per acre for fungicides 
to treat spinach seed has given increased yields valued at $50 to $300 per acre. 
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