APPEl^DIX VII. 



COLOEADO DATA FOR 1877. 

 SPECIAL EEPORT FROM WILLIAM HOLLY, DEL NORTE. 



Prof. C. V. Riley, Chief United States Entomological Commission: 



Sir : I have tlie honor to state that, in obedience to your instructions, I have visited 

 personally most of the country lying south of an east and west line drawn through 

 Colorado Springs, El Paso County, Colorado. My investigations under your letter of 

 instructions were confined to a few days in May, the month of June, and part of July, 

 1877. I had previously, during the summer of 1876 and spring of 1877, passed over 

 most of Southern and Southwestern Colorado, and having made notes of the ravages 

 of the grasshopper for newspaper correspondence, I am able to speak from personal 

 knowledge of investigations and researches prior to the date of May 20, 1877. 



I started from Del Norte the first week in June, passing down the Rio Grande Val- 

 ley (crossing the San Luis Park from west to east), to Fort Garland. The valley is 

 devoted to agriculture and stock-growing, and most of the bottom lands are fenced. 

 The grasshoppers have done but little injury in past years and none during the pres- 

 ent season. Ute Valley, extending from the Rio Grande to the Sangre de Christo 

 Range, a beautiful cultivated section, has been singularly free. Crossing the Sangre 

 de Christo Range at the pass of that name, the first point is La Veta, the principal 

 place in Huerfano County, and at the head of the Cuchoras Valley, one of the finest in 

 Southern Colorado. In previous years great ravages have been committed in this 

 valley and along the base of the range to the Arkansas. The Cuchoras Valley is prin- 

 cipally inhabited by Mexicans, who use no precautionsforpreventing hatching, growth, 

 or destruction, except acequias for irrigation. Along the eastern base of the Sangre 

 de Christo a crop of grasshoppers which hatched in the latter part of April and eaily 

 part of May were destroyed by severe rains followed by sharp frosts. The eggs for 

 this crop were deposited by locusts late in the fall of 1876, when the ground was warm 

 and almost ])are of vegetation. The winter was open and mild and the spring early 

 and hot, causing a premature hatching. The young appeared in immense numbers, 

 but disappeared after the rains and frost spoken of. A second crop appeared and 

 were active during my visit here in June, but in small numbers, and were generally 

 found attacked by the Rocky Mountain grasshopper parasite. But little damage has 

 been done in this county the present season. 



I proceeded to Colorado Springs by rail, and after ascertaining that I was too late 

 to investigate the early and too soon for the later or midsummer crop, I made very 

 complete arrangements to have thorough reports made in readiness for your coming 

 later in the season. 



At Pueblo similar arrangements were made, as it was almost impossible to see farm- 

 ers and stock-men on account of their absence at the annual round-ups. 



I had previously made an extended trip through the Arkansas Valley from near 

 Grenada to Canon City. In 1876 the valley was visited by several swarms of grass- 

 hoppers, the last depositing vast quantities of eggs, which, at the time of my trip, 

 March 12 to 20, 1877, were just beginning to hatch. There have been no artificial 

 means used in this valley for prevention or destruction, and the plains have afforded 

 excellent hatching-grounds. In past years Fremont, Pueblo, and Custer Counties have 

 suffered very considerably. 



I returned to Del Norte and passed up the Rio Grande Valley as far as farms extended, 

 and crossed the range to Lake City. In previous years, from 1872 to 1876, this section 

 has been periodically visited. Last year the upper valley of the Rio Grande suffered 

 severely. The grasshoppers came from the northwest, across the range, making long 

 flights, and swooping down in immense numbers, destroying every living thing, and 

 attacking the cottonwood and willows. This season they hatched in small numbers 

 in the valley of the Francisco, Pinos, Cebolla, and elevated exposed portions of the 

 range. The prevailing direction of travel has been both east and west. Finding 

 it difficult to travel with the conveyance I had, I returned to Del Norte and procured 

 a saddle-horse, crossing the San Luis Park three times on my way to Park County. In 

 1876 Saguache County suffered from two different swarms, and this season grasshoppers 



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