REMEDIES. 45 
degrees south to the vicinity of Evansville, IimI., we .should expert about t In- 
same condition of the Hessian fly during the first week of October; that is, if we 
pass the danger line about the second week of September in southern Michigan, we 
should expect to encounter it again in southern Indiana in the first <>r second week 
of October. A considerable correspondence and my own experiments indicate that 
this is easily true. 
Evidently there will be considerable seasonal variation, so that these 
dates must be taken subject to slight changes in either direction, but 
it may be assumed that the earlier or later appearance of the brood 
will depend upon the character of the season in moisture and warmth, 
so that if the weather remains unusually dry and hot the fall planting 
should be proportionately delayed, while if conditions favor an early 
emergence a crop may be planted somewhat earlier. Taking the lati- 
tudes mentioned as a guide, the farmers of the winter wheat belt 
through Illinois, Missouri, southern Iowa, Nebraska, and Kansas can 
determine pretty accurately as to the proper time for seeding. 
INTERMITTENT WHEAT CULTURE. 
While the Hessian fly is a winged insect and capable of traveling to 
some distance, the fact appears to be that it prefers to deposit its eggs 
in the immediate vicinity of the place of its emergence. This is con- 
sidered especially true of the adults from the spring brood, which are 
supposed to select the tillers in the field where they emerge rather 
than to scatter to adjacent fields. The interruption of wheat culture, 
therefore, for one or two seasons, even if adopted on a single farm, 
will have an appreciable effect in preventing injury to the crop in after 
years. A suitable rotation, even as applied to a single field, is counted 
as serviceable in the reduction of Hessian fly injury. It communities 
can adopt a uniform system of rotation or alternation of wheat crops 
with crops that are not capable of supporting the Hessian fly they 
should secure almost perfect immunity from tins pest. In fact, tins 
seems to me to be practicably accomplished throughout a large part of 
the State of Iowa, where wheat is grown as an occasional crop and tin' 
Hessian fly has been practically unknown since the early settlement of 
the State. 
PASTURING Willi SHEEP. 
One of the methods suggested in the early history of the Hessian fly 
problem was that of pasturing the winter wheat for the purpose of 
destroying the larva'. The first published account of the insect states 
that by feeding thecrop very close in winter and spring, if the land is 
rich it will again spring up and the worms do not much injure the 
second growth. If practiced at the right time it is possible that the 
eggs might be nipped off and devoured with the leaves, but if it is 
remembered that the eggs usually hatch within four days alter deposi- 
tion, that the plants at this time would furnish rather limited pasturage, 
aud that the larva' soon after hatching make their way down to the 
