OF THE FARM AND GARDEN". 



271 



thej do in some of the valleys, up to the altitude of seven 

 or eight thousand feet — possibly sometimes to nine thou- 

 sand — but they usually come out so late that the frosts 

 of the following fall catch them before they take flight. 

 As an illustration, the Middle Park of the Eocky Moun- 

 tains is a great basin, bowl-shaped, with a single line, 

 broken out of its western rim. Otherwise, it is surround- 

 ed by snowy mountains. Fifteen years ago, it was in- 

 vaded by Grasshoppers from the direction of Utah, 

 which deposited their eggs all over it. In its lower por- 

 tion the young began hatching about the first of July. 

 They attained maturity and took flight in August. 

 Their hatching ground was from six to seven and a half 

 thousand feet above the sea. Further up toward the rim 

 they came out later, and at nine thousand feet they did 

 not appear until the last of August. September frosts 

 and snows caught them, and they never left their native 

 ground. About the same time these latter hatched, im- 

 mense swarms of full-grown insects came again from the 

 west, but instead of lighting in the Park they drifted up 

 against and upon the snowy range east of it, where they 

 perished in countless millions. 



In August, 1864, this country had its worst visitation 

 of "Hateful Grasshoppers." They had hatched in the 

 valleys of the Upper Missouri, from six hundred to eight 

 hundred miles distant, and swept over Colorado with a 

 solid front. They ate up late crops and then deposited 

 their eggs and died. In the following spring, their pro- 

 geny came out of the ground with the early crops, which 

 they devoured. When about one-third grown they were 

 attacked by an Ichneumon Fly, which stung them in the 

 back, depositing one or more eggs. The product of these 

 destroyed probably one-half or two- thirds of the Grass- 

 hoppers, and the balance in due time took flight and left 

 us. With the exception of those two years, Colorado has 

 not been generally nor severely scourged by that pest. 



