NIAN INSTITUTION LIBRARIES 
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crop and attacks it early in spring, when, unless the a enemies 
come to the fore, it multiplies in great abundance. In the writer’s 
experience the lady birds and other enemies soon gain the ascendancy 
and become so abundant that they are forced to migrate for food. 
The trap crop will ordinarily remain in condition to sustain aphides 
and their enemies until melons or other crops susceptible to melon- 
aphis damage have past the danger stage and are ripening. 
The farmer may exercise his own judgment in regard to the loca- 
tion of the trap crop. The writer believes that the greatest advantage 
would accrue from planting three or more rows of rape or kale on 
sxach side and, in the case of fields of more than 4 or 5 acres, by plant- 
ing additional rows between. Planted on all sides, the trap crop will 
attract aphides and their enemies from every direction, and this result 
will be facilitated by permitting the growth of weeds between the 
rows. In fact, weeds are a desideratum in these operations, since 
they furnish the best natural hibernating places for the ladybirds and 
similar beneficial insects. It is advisable also to place boards, loose 
bark, or hollow logs about the margins of the fields to secure better 
facilities for hibernation. As fast as one crop of rape, or whatever 
is used, matures, or its growth is stopt by the aphides (as might 
sometimes happen), another planting should be made so as to keep a 
constant supply of cabbage aphides on hand that the natural enemies 
may not migrate to other quarters. 
CONCLUSION. 
Many of the remedies that have been indicated as of service in the 
control of the melon aphis (with the exception of the last) operate 
against most other cucurbit insects, several species of which are 
usually present. Thus the kerosene emulsion and soap solutions kill 
young squash bugs and act as deterrents to most other insects, and 
bisulfid of carbon will kill other soft-bodied insects besides the aphides, 
while fall plowing and clean cultural methods are valuable in destroy- 
ing the squash-vine borer. Tobacco fumigation, however, has little 
effect on these other insects as they occur in the field. 
Approved: 
JAMES WILSON, 
Secretary of Agriculture, 
Wasuineton, D. C., November 14, 1906. 
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