512 
JOURNAL OF ECONOMIC ENTOMOLOGY 
[Vol. 16 
' State Department of Agriculture in the fall of 1919, have definitely 
established its limitations as a factor in the control of that pest. They 
have also corroborated, to a large extent, the results of the work carried 
on in the early experimental plots and have brought to light a factor, 
secondary parasitism, which it was hoped might be avoided. 
As has been fully explained in the earlier reports of the introduction and 
establishment of this parasite, two distinct field conditions termed 
“uneven hatch” and “even hatch,” required consideration in determining 
to just what extent it might become a factor of control. These two 
field conditions, the first of which embraces the coastal areas in which 
the scale has one or more overlapping generations, and the second, the 
interior areas with a single uniform, generation must still be considered 
separately in recording the present status of this parasite. 
Coastal or “Uneven-hatch” Conditions 
At the time of its introduction it was obvious that the mild climate 
of the coastal areas together with the overlapping generations of the 
black scale, offered an ideal condition for the Aphycus to gain the as¬ 
cendency through rapidly succeeding generations, if it was at all adapted 
to California’s climatic conditions. Little surprise was occasioned, 
therefore, among those carrying on the work at the rapidity of its spread 
and the apparent thoroughness of its work in these areas when once 
established. Appreciating, however, from previous experience with such 
problems, that newly introduced insects often have an immediate 
“flare-up” which they are unable to maintain through succeeding seasons, 
every effort was made not to create any undue enthusiasm among the 
growers, and in fact this policy was so closely adhered to that it reacted 
to the extent of the growers taking matters into their own hands. The 
efficiency of the Aphycus was so obvious to them that they hailed it as a 
second Vedalia. Wide-spread distribution of field-collected parasites 
was made through their own organizations. Large tracts of orchard 
were allowed to go untreated otherwise, in many cases successfully the 
first two seasons; later, however, there was a heavy loss from the 
smutting of the fruit and foliage from a heavy infestation of scale; sale 
of fumigation tents was even considered but fortunately never carried out. 
Burdened with an annual fumigation bill running well into seven 
figures, the growers are perhaps not to be blamed for grasping at such a 
promising “straw” in their efforts to reduce costs. It is with regret 
that I find it necessary to record that a factor, secondary parasitism, not 
entirely unexpected but one which it was hoped might be avoided, has 
entered into the question and has reduced the efficiency of the Aphycus 
