(")(') ANNUAL REPORTS OF DEPARTMENT OF AGRli OLTURE, 19S1 
Surveys outside the known infested areas revealed infestations in 
fawv counties. The new finds were in areas adjacent to infi 
count ies. 
Other surveys to determine the abundance of beetles Bhowed that 
numbers in all infested areas are lower than in prei ioua This 
reduction is believed due to the cumulative effect of DDT treatments 
of soil in nurseries and on farms, supplemented by DDT foilage 
sprays. 
Extensive Farm-Land Arras Treated to Destroy White-Fringed 
Beetles 
With the completion of soil treatments this year, -nine 38.000 acres, 
or about half of the farm land- known to be infested with white- 
fringed beetles, have been treated with DDT at the rati' of 10 pounds 
an acre. The work has been in progress since l^K*. This dosage will 
control the beetle for approximately 6 years. Farmers were urged 
id supplement the residues in the treated fields by adding DDT to 
the commercial fertilizers applied in the fields. About half of the 
acreage that had been soil-t reated received a supplementary treatment 
of DDT mixed with commercial fertilizer. By following a program 
of annual applicat ions of DDT with fertilizers it is anticipated that it 
will be possible to keep the DDT residues high enough to prevent 
reinvasion of treated fields. 
DDT Treatments of Soil Qualify Some Crops for Certification 
Treatment of infested farm land with 10 pounds of DDT an acre 
was approved as a condition for the certification for interstate move- 
ment of soybeans, lupine, [rish potatoes, and grass and Legume seed. 
A waiting period of approximately 1 year following the treatment is 
required before crops produced on the land are eligible for certifica- 
tion. Approximately i" 1 percent of the infested farm land in Alabama 
devoted to the production of [rish potatoes and a sizable portion of 
the soybean land have been treated. Farmers readily accept the treat- 
ment, for it economically protects their crops against injury by the 
beetle larvae and at the same time renders their crops eligible f<w 
movement without further treatment. 
Alternate for DDT as Certification Treatment Sought 
Chlordane added to nursery soil a year ago at rates of 5 or more 
pounds an acre prevented the establishment of white-fringed beetle 
larvae. Certain plants intolerant to DDT tolerated the chlordane 
treatment in plot tests. These observations were made as part ^( 
continuing investigations to determine whether chlordane can be used 
alternate to DDT at 50 pounds an acre, now authorised for cer- 
t ificat ion under I he regulat ions. 
[\ i to determine tne tolerance of st rawberry plants to such DDT 
treatments showed that DDT prevented normal plant development 
and reduced berrj production. The reduction in yield was directly 
proportional to tne amount of DDT added to the soil. At 50 pounds 
an acre there was a one third reduction m Field. 
