304 REPORT UNITED STATES ENTOMOLOGICAL COMMISSION. 
By K l'. iciK <■ to the map of your State, prepared by your Geological and Natural 
History Survey, showing the locust areas therein for the years 1873-70, it will be seen 
that the southwestern portion of the State was the part most continuously affected. 
Other facts ascertained by the commission indicated some peculiarities in Ibis respect 
in reference to t his section not observed in other partsof the State 01 in the Slates south. 
These facts attracted my attention and induced me to seek and, if possible, to Gnd out 
the cause for these peculiarities ; in other words, to find why the locusts hung longer 
and more continuously around this section than in other portions of the State. This, 
I now believe, is to be found in the elevated region called the Coteau of the Prairies, 
which affords topographical and climatic conditions more nearly adapted to the con- 
tinual cxisienee of tin- locust than other port ions of the State. If I am correct in this 
opinion we have here one factor which must be taken into consideration in the dis- 
cussion of this locust problem so far as it relates to your State and the adjoining sec- 
tion of Dakot a. 
As before intimated, I had formed the idea that the more elevated portions of Eastern 
Dakota, for instance, those lying along and bordering the valley of James River, were 
too sterile and arid ever to be used for agricultural purposes; that in fact but a narrow 
strip alone along t lie James River could he made productive by means, in part at least, 
of irrigation. The facts seen and ascertained the present year have in a large meas- 
ure dispelled this unfavorable opinion. I am aware the present year is a very favor- 
able one, and one that cannot be considered as a type of the seasons in that section; 
but it shows, I think, conclusively, that a very large portion of this section of Dakota 
can and will ultimately be made to sustain a large agricultural population. For even 
allowing quite a heavy discount on the present crop there would still be sufficient to 
justify farming in this region ; and wherever this is the case, and the process of fann- 
ing is so easily carried on as here, the section will ultimately be settled tip. 
In this fact I think we find a second important factor to be considered in discussing 
this problem. 
A third possible factor is the supposed climatic change believed by many to be go- 
ing on. Although I have not included this item in the present consideration, and can- 
not say that I have been couverted to that view, but look upon these changes rather 
as cyclical, yet there are some reasons for believing that an unusual change of some 
kind is now going on in the seasons in the Northwest; what the ultimate result will 
be I am wholly unable to predict, but so far, at least, it is favorable. 
Leaving t he last item out of the discussion let us see what hope is to be based on the 
other items. 
It is reasonable to believe, in fact we may assume as evident, that the farther west 
settlements are pushed continuously, that is without extensive breaks, and the denser 
they become, the greater will be the tendency to hold back, so to speak, the locust 
swarms ; that is to say the advanced cultivated fields will bring them down, in part 
at least, and, supplying their appetites, prevent them from advancing further eastward ; 
their temporary nesting grounds will also be disturbed, and thus fcheir advance re- 
tarded. 
While this is true theoretically, the experience of the years 1*74-77 may cause many 
to doubt its correctness in reality. It is true that swarms drive on southeast in their 
invading flights overbroad and extensive settlements, as, for example, over Nebraska 
into Iowa and Kansas, and occasionally even into Missouri and Texas ; but after all, 
though not brought to public notice, the fact is that Northern or Northeastern Ne- 
braska often receives the smaller invading swarms and suffers the injury when the 
central and southeastern parts are entirely exempt. Other facts might also be cited to 
prove that the statement above made is true as a general principle. But Minnesota 
is somewhat peculiarly and favorably situated in this respect. The locust swarms, 
as a very general rule, sweep down from the northwest in a south and southeast direc- 
tion, and, as it requires a much less opposing influence to turn them slightly away 
from their course than to stop them directly, the chances are much more in favor of 
localities thus situated than if placed directly in the line of their usual course. 
