million acres of intertilled and drill-seeded 
cultivated crops each year. The intertilled row 
crops receive two to five seedbed tillage 
operations and an average of about five cul- 
tivations each year, In addition, nonchemical 
methods of weed control are used on a high 
percentage of the more than 1 billion acres of 
forage and grazing land. Weeds are also con- 
trolled on millions of acres of noncrop land 
each year, 
Seedbed preparation, cultivation, and weed 
control require the use of 4-1/2 million farm 
tractors that supply 120 million horsepower 
in moving more than 250 billion tons of soil 
each year. This amount of soil would make a 
ridge 100 feet high and 1 mile wide from New 
York to San Francisco. This is the largest 
materials-handling operation in the world and 
the costs are enormous. About one-half of 
this operation is practiced solely for the con- 
trol of weeds (3). 
In 1962, cultural and other biological or 
nonchemical methods of weed control were 
used on about 75 percent of the national crop 
acreage, Chemical methods, combined with 
cultural practices, were used on about 25 
percent (8, 9). Herbicides were used on more 
than 70 million acres of agricultural land in 
1962 at a cost of more than $272 million, as 
compared with 53 million acres treated in 
1959 at a cost of almost $128 million (table 1). 
This amounted to a 33-percent increase in the 
acreage treated with herbicides in the 4-year 
period, Expenditures for herbicides increased 
112 percent during the same period, 
Not only has the acreage treated with 
herbicides increased each year, but a greater 
diversity of herbicides is available today than 
ever before. In 1944, for example, there were 
only about 14 herbicides; in 1964, farmers 
had a choice of about 125 basic herbicides 
available in about 8,000 registered products, 
The widescale use of herbicides during the 
past 20 years, their advantages and disad- 
vantages, progress made in weed control by 
their use, and problems evolved during this 
period provide a partial basis for considering 
the characteristics needed in herbicides of 
the future. 
CHARACTERISTICS OF 
HERBICIDES IN THE FUTURE 
The characteristics of herbicides in the 
future will be determined by the chemical 
Table 1.--Comparison of estimated extent and costs of chemical weed control in United States, 1959 and 1962+ 





AB Acreage treated by-- 


























States Total area Harvested sew TOUaL Cost obealT Average cost per acre of 
Reporting treated treated herbicides and all treatments FR Custom 
Pp = applications S Sig aa oe he operators 
1962 1959 1962 1959 lie 1962 1962 1959 | 1962 Change 1959 1962 1959 1962 
— i 
1, 000 1,000 , 4700 Sarai |(poncont || perc e cen 
Number | Number acres acres Percent | Percent O | $1,000 Dollars | Dollars | Percen Percent | Percent | Percent | Percent 
46 20,051 25,302 24.5 38.8 37,980 57,600 1.89 2.28 20.6 82 83 18 17 
15 1,554 5,433 10.3 34.9 4,628 16,805 2.98 3.00 3.7, 92 91 8 9 
15 28 556 2,827 2.5 10.2 2,315 10,835 4.16 3.83 -7.9 98 90 2 10 
38 45 20,723 18,931 21.6 23.5 37,095 29,579 1.79 1.56 -12.8 Te) 65 25 35 
4 6 502 940 shlsy) 53.0 888 6,250 1.77 6.65 275.7 13 66 87 34 
5 8 35 320 2.4 22.0 116 2,565 3.33 8.27 149.8 100 97 (3) 3 
11 15 125 362 13.8 32.8 625 2,237 5.05 6.18 23 94 65 é 35 
14 25 2,093 2,665 13.6 23.1 6,512 5,258 3.11 1.97 -36.7 40 65 60 34 
Forage seeds...... 14 20 282 439 7.8 16.0 1,868 2,416 6.62 5.50 -16.9 80 62 20 33 
Vegetables........ 20 29 276 951 959) 3555 1,418 8,634 5.14 9.09 76.7 84 75 16 25 
Potatoes.........- == 4 == 171 -- 12.3 1,017 = 5.95 a ce 100 -- fe) 
Dry beans......... -- 2 -- 16 -- 1.1 114 -- 12 -- -- 95 -- 5 
Sweet corn.......- -- 1 -- 30 -- 4.6 187 -- 6.23 -- -- 95 -- 5 
i 27.0 ( -- -- 98 -- 2 
o.7 4.4 99 86 1 14 
- -- 97 -- 3 -- 
24. -15.6 70 34 30 6¢ 
O. 39 81 78 19 
24.9 -- -- -- -- 
+= + 
TAWDS's os cjc'cc cece vie 17 22 60 672 -7.9 2 83 18 17 
PaStureS...-.eeeee 34 45 2,400 4,714 17.4 4, 64 2€ 36 
Rangeland......... B 20 2,011 2,262 -9. 37 zy 63 6 
Forest plantings.. -- 18 -- 274 -- -- -- -- - 
Noncropland....... 27 31 1,971 3,612 131.6 30 34 
ae =; i + T 
Subtotal.... -- -- 6,442 11,534 104.5 Jed == ~—— =— 
Ee +— + +— =+- 
Grand total. 41 50 52,923 70,667 58.8 -- -- -- -- 
1 











? Pata summarized from reference 9. 
“ less than 0.5 perce 
3 Excludes treated acreag 

