BUREAU OF ENTOMOLOGY AXD PLANT QUARANTINE 00 
in these alternate hosts is dependent on the proximity of the plants 
to infested cotton, intensity of the infestation in cotton, and the fruit- 
ing condition of these plants at the time the cotton is destroyed. 
Thus far chemical treatment of the soil has not proved an effective 
or inexpensive means of controlling the pink bollworm. Of the vari- 
ous insecticides tested. DDT and BHC have given the highest larval 
kill. Dosages needed for any appreciable kill, however, would be too 
costly. 
Greater impetus will be given to pink bollworm research in the next 
fiscal year. A tentative allotment of $110,000 of Bureau funds has 
been made to that activity through a shift of funds from less urgent 
problems. Matching funds are being sought from several State and 
nongovernmental sources. Plans are also being developed for an 
expanded 5-year research program. 
Many Florida localities freed of wild cotton host plants 
Work aimed at eradication of the pink bollworm in South Florida 
was effective in freeing many localities of wild cotton host plants. 
Searches for such wild cotton plant- in inaccessible coastal and island 
areas covered more than 11.000 acres and resulted in destruction of 
some 30,000 wild cotton plants. Four percent of the plants destroyed 
had matured fruit. Examination of 9.400 bolls, blooms and squares 
from these plants showed a very low pink bollworm infestation — only 
73 larvae having been found. The previous year 571 pink bollworms 
were found during the examination of 13,500 fruiting forms. In 
addition to the survey for wild cotton plants. (370 dooryard locations 
were checked and 3.085 dooryard cotton plants removed from 410 
of them. Scouts engaged in this work found 316 pink bollworms in 
some 19,000 fruiting form- collected from dooryard cotton plants. 
Many small locations were found entirely free of wild cotton plants. 
That part of Florida north of the Cape Sable area on the West Coast 
and Broward County on the East Coast were found free of pink boll- 
worm infestation, thus assuring a safety zone between the surveyed 
area and the domestic cotton-producing area farther north. 
As a result of the discovery in Texas that kenaf — a fiber crop new 
to this country — is a host of the pink bollworm. the Florida survey 
crew inspected a large kenaf acreage adjacent to known pink boll- 
worm infestations. A method of inspecting such seed for pink boll- 
worm was developed. Several hundred pounds of seed was inspected 
and found free of infestation. 
Less Boll \$ eevil Damage to Cotton Crops 
Widespread use of large quantities of insecticides early in the 1951 
growing season combined with hot. dry weather from June to August 
resulted in much less damage to the cotton crop than in either 1919 
or 1950. 
The general cotton insect survey in 1951 included specific counts 
on the boll weevil and other cotton pests. Plant inspections were 
made early in the season and the regular square infestation counts were 
made during the cotton fruiting period. The survey during the 1951 
growing season >howedthat the weevil survived the winter in sufficient 
numbers to cause serious damage in most areas where it occurred in 
