
nn ae 
E. A. MoGregor reports that an unusual type of attack by citrus 
thrips has developed at Lindsay, Calif. He says: "A marked lack of 
foliar development has caused the thrips to turn their attention chiefly 
to the fruits--in spite of the fact that the oranges were rapidly siz- 
ing and toughening. This condition has resulted in more than a normal 
amount of the superficial or 'silvering' type of injury to the rind. 
As a consequence, we have had to revise our opinions regarding the dura-— 
tion of time that the citrus fruits are susceptible to damage by the 
maraips. " 
Reporting on control of the soft brown scale (Coccus hesperidum 
_L.), Mr. McGregor says: "Developments during the past two months have 
tended to refute the idea that the generous use of sulphur interfered 
with the work of scale parasites. There has been very general dusting 
during 19351, but in spite of this the soft brown scale has. been nearly 
Wiped out. A high percentage of the scales large enough to support 
parasites exhibit the exit holes. This objection to sulphuring has evi- 
dently been disposed of." 
C. F. Doucette, Sumner, Wash., reporting on vapor treatments with 
commercial stocks of bulbs, says: "To September 1 the amounts treated 
are as follows: Laboratory equipment: 162 tons narcissus bulbs, 40 
varieties; Van Zonneveld equipment: 278 tons narcissus bulbs, 25 varie- 
ties. Treatment will continue through September. Bulbs treated at tem- 
peratures up to 115° F. for 4~hour periods on August 29 and 350 show no 
external signs of injury September 1. Bulbs treated at periods of 4- 
6-8-10-12 hours at 111° on August 17 show no external signs of injury 
on September 1." 
H. H. Richardson, reporting on experiments with pyrethrum and other 
insecticides at Washington, D: C., for the month of August says: "The 
combination sprays consisting of alcohol extracts of pyrethrum with di- 
lute soap solutions were found to be ineffective for the control of green- 
house mealybugs (Pseudococcus citri Risso). Only the very immature in- 
sects were killed by these sprays, even when strong concentrations of 
pyrethrins (0.0270) were used. Emulsions of highly refined petroleum 
oils were found to be much more effective for mealybug control. The 
pyrethrin-soap sprays were very toxic to sowbugs (class Crustacea) when 
used at strong concentrations." 
TRUCK-CROP INSECTS 
Reporting on studies of soil insects at Walla Walla, Wash., 
M. C. Lane says: "There has been only a trace of rainfall at the labora- 
tory during August and the temperature has been slightly above normal for 
this vicinity. The wireworms have been kept fairly deep in the soil and 
have not done any damage to crops, except potatoes. Damage to potatoes 
is largely done at this time by puncturing the new tubers and ruining 
them for marketing. The shade furnished by the potato vines, together 
With the irrigation water applied regularly, keeps a condition of soil 
around the tubers that is very favorable for the wireworms to work." 
