wae FARMERS’ BULLETIN 657. 
the whole system is complete, and the chinch bugs can be thus shut 
out from the first.' 
With these barriers of either ridge or furrow and the use of coal 
tar or crude petroleum, supplemented by kerosene emulsion, a very 
large percentage of the injury from chinch bugs may be obviated, 
and, in fact, with a reasonable degree of watchfulness and prompt 
action all injury from migrating hordes may be prevented. The use 
of tarred boards set on edge or slightly reclining might, under some 
circumstances, take the place of the ridge or furrow, but these cases 
will be exceptional, and the use of kerosene emulsion will probably 
be found equally practicable here, as also will the post holes for 
collecting the chinch bugs. This method is merely cited in order 
to call attention to its possible use where the others are found imprac- 
ticable. 
THE USE OF FURROWS WITHOUT PETROLEUM OR COAL TAR. 
The plowing of furrows (fig. 9) has been in vogue since the first 
writings of Le Baron and the second report of Fitch, and may be 
utilized in other ways than those previously mentioned. A heavy 
log or other cylindrical object of the proper size dragged back and 
forth in this furrow will pulverize the soil in dry weather, and Dr. 
Forbes has recorded the fact that where this furrow has a tempera- 
ture of 110° to 116° F. it is fatal to the young bugs that fall into the 
furrow, even if they are not killed by the log. As 120° is not 
uncommon in an exposed furrow on a hot summer day, it will be 
observed that there may be cases where this method will be found 
very serviceable, and especially is this likely to prove true in a sandy 
soil with a southern exposure. In sections of the country where 
irrigation is practiced, these furrows may be flooded and in this 
way rendered still more effective without the expenditure of either 
time or money to keep them in constant repair. Riley long ago laid 
considerable stress on this measure, believing it of much value, espe- 
cially in the arid regions of the far West. The same writer advised 
the flooding of infested fields, wherever it could be done, for a day or 
so occasionally during the month of May. It is hardly probable, 
however, that this will often be found feasible except in rice fields, 
where it is sometimes practiced. 
NECESSITY FOR PREVENTING CHINCH BUGS FROM BECOMING ESTABLISHED IN 
FIELDS OF WHEAT AND GRASS. 
In the foregoing it will be observed that prevention of migration 
has been the chief end in view, either by destroying the chinch bugs 
in their hibernating quarters, and thus preventing the spring migra- 
tion to the breeding places, or by various traps and obstructions to 
prevent them from migrating from such places to others not already 
1 Snow, F. H. Contagious diseases of the chinch bug. Uniy. Kans. Exp. Sta. Fifth Ann. Rpt. of the 
Director for the year 1895, p. 45-47, 1896, 
