PAST HISTORY OF THE ROCKY MOUNTAIN LOCUST. 53 



CHAPTER II. 



CHEONOLOGICAL HISTORY. 



The history of the American or Eocky Mountain locust is in nearly 

 all respects parallel with that of the locust of the Old World. It breeds 

 over a large continental area, and periodically, in seasons of extreme 

 drought and other favoring meteorological conditions, migrates in im- 

 mense hordes for several hundred miles beyond its usual habitat. 

 Unlike the locust of the Eastern Hemisphere, our species naturally 

 affects the cooler and more elevated portions of the temperate zone in 

 the New World, though its southern limits extend at times into the hot 

 and dry plains of the Great Basin. 



Fitful and periodical inits visits to the older, settled portions of the West, 

 thehistory of the Rocky Mountain locustisdifBcult to trace beyond aperiod 

 of about thirteen years. Previous to the year 1864 it has been rarely 

 referred to by travelers in the West, and after examining the reports 

 of the government expeditions and the works of Lewis and Clark, Pike, 

 Irving, and others, we find little or no mention made of it. It is a ques- 

 tion in our mind whether in some regions it may not have increased in 

 numbers since the Far West has been partially settled, particularly in 

 those regions where irrigation has been practiced, as in Utah and Colo- 

 rado and in the western edge of the Mississippi Yalley, as in Nebraska, 

 Kansas, Iowa, and Minnesota 5 but this is entirely uncertain, and it is 

 more reasonable to suppose that as the Western Territories become more 

 thickly settled the numbers of locusts will become diminished. 



In treating of the history of locust invasions, we will first consider the 

 subject in a very general way, and then state the facts more concisely, 

 arranged according to separate States and Territories; and, thirdly, 

 present a summary of the subject in a tabular view. The latter is cal- 

 culated to send a chill to the agricultural heart when one sees how dense 

 the figures are from 1864 until 1877, and to lead one to infer that the 

 evil is waxing greater and greater as the years go on. This may be 

 due, however, to the greater extent of the country settled and to the 

 fact that the population is growing denser and denser. However that 

 may be, we shall deal with facts and not with theories, and would 

 remind the reader that in a number of the years there recorded large 

 harvests resulted, the injury done by locusts being local and only con- 

 fined to a portion of the season, while in 1877 the largest wheat harvest 

 ever grown was safely harvested. 



Leaving out of account the locust visitations in the Atlantic and 

 Pacific States, which were made by difierent species from the Rocky 

 Mountain locust, the first authentic statement is to be found in NeilPs 



