- 72 - 
The Florida Agricultural Experiment Station ( 105 ) in 1937 reported 
that sulfur dusts containing pyrethrum gave an immediate kill of jassids 
far superior to that obtained with sulfur dusts containing rotenone. 
However, a week after the applications wore made there ras little differ- 
ence between the pyre thrum- and rotenone-dusted plots, though the advantage 
was in favor of the pyrethrum. 
Cicadidae 
Magicicada sept endecim (L.), the periodical cicada 
Cory and Knight (_56_) in 1937 reported that Fed Arrow at a dilution 
of 1:400 killed 100 percent of all periodical cicadas hit. Spraying at 
night is preferable, as cicadas fly too actively during the day to permit 
of success then. Potenone [derris?] alone (4 pounds) and with Penetrol 
(l/2 gallon) per 100 gallons of water gave 25-percent kill. 
Coccidae 
Aonidi ella aurantii (Mask.), the California red scale 
R.H. Smith (24-6) in 1929 made tests against the California red 
scale on lemon trees with nicotine and extracts of pyrethrum, derris, 
three species of Tephrosia, and two species of Lonch o carpus , in a highly 
refined kerosene. l'6~^~omb~i.na t i on showed any p r a ctTca 1 va 1 v 1 , e . 
Smith (247) in 1932 described attempts to increase the effective- 
ness of highly refined spray oils by incorporating toxic substances 
(called "toxicants'') in them. Laboratory tests were made with kerosene 
and mineral-seal types of oil on (Chrysomphalus) Aonidiella aurantii, 
and orchard tests were made in which light-medium and medium spray oils 
•■ere used. Among the toxicants tested in a highly refined kerosene 
(viscosity 30 seconds, 98 percent unsulfona table, and applied as a mechan- j 
ical mixture in water without emulsifier) were nicotine, pyrethrins, 
rotenone, and various extracts of pyrethrum, Der ris elliptica, three 
species of Tephrcsia, Lcnchccarpus sp., and haiari. Butyl phthalate 
increased the solubility of rotcn one in the oils. Smith concluded that 
the attempts to iucrease the effectiveness of spray oils by the use of 
toxicants, in the experiments with the California red scale, were 
unsuccessful , 
Tox-X or Ortho Derris plus a reduced dosage of oil is decidedly 
loss effective than the regular oil sprays against the red scale. — 
Cali&ornia Fruit Growers' Exchange (34) in November 1935. 
In the August 1936 issue of their Pest Control Circular (35)" 
:"k ■■; so-called nonoil sprays, the California Fruit Growers' 
Exchange stated that Ortho Derris and Tox^X arc composed of a powdered 
insecticide containing derris added to a low dosage of light medium oil, 
usually l/2 to 2/5 percent. At the lower dosages of oil, these derris 
combinations have had little effect against the red scale. They cost 
several cents a tree more than oil sprays, "where used with light-medium 
oil at strengths as high as 1-1/2 percent, the cost approximates that 
