36 SOME INSECTS INJURIOUS TO TRUCK CROPS. 



DISTRIHUTION. 



This leafhopi^er is apparent^ a native of the southwestern part 

 of the United States. It has been collected from about the region 

 of Denver, Colo., south along the edge of the mountains, through 

 New Mexico, and west through Arizona, Utah, and southern Idaho 

 to the coast • in California and Oregon. Though confined to the 

 mountain region, its distribution is restricted to the lower levels, 

 and it is never taken on the mountains themselves. From this region 

 it has not spread very far up to the present time. It was taken at 

 Fort Collins and Lamar, Colo., in 1901 — in one case 100 miles north 

 of its known habitat, on wild plants, and in the other an equal dis- 

 tance east, but was rare in both situations. In Utah it has spread to 

 the northern line of the State and into Idaho as far as that par- 

 ticular beet area has been extended, while it has not as yet been taken 

 from the wnld plants north of Ogden, Utah. 



LIFE-IIISTORY STUDIES. 



Search was made for this species as soon as the growing season 

 commenced in the spring of 190G, but no specimens were discovered 

 in the Cache Valley, Utah, up to the time the beets came up. A 

 trip to Sevier County, Utah, at the time the very earliest beets 

 were just showing (April 22) failed to disclose a single individual, 

 either in the beet fields or in waste places or hedgerows adjacent to 

 the beet-growing districts. The first specimens discovered this sea- 

 son W'cre found at Thompsons, Utah, May 3, feeding on Russian 

 thistle, and a few days later the insect was found on the same plant 

 and on an annual saltbush (Atriplex) at Grand Junction, Colo. 



Beet fields w^ere examined at Grand Junction, Colo., May 8, and 

 in Utah at Lehi, May 9; Smithfield, May 12; Garland, May 13; 

 Lehi, May 17; Corinne and Penrose, May 22; and Provo and Lehi, 

 June 1, without finding a single leafhopper on any of them. The 

 beets w^ere not up at Lehi on JNIay 9, nor at Smithfield, but the fields 

 were examined carefully, especially where weeds were beginning to 

 appear. Fields at Logan, Utah, were under observation during all 

 this time and up to July 1, but no leafhoppers were found. 



RECORD AT LEHI, UTAH. 



On June 21 a field was examined at Lehi in which there w^as an 

 average of one or two leafhoppers to a beet. They were all adults 

 and two-thirds of them females. The beets in this field were from 

 6 to 10 inches across, and no sign of injury was observed. On exam- 

 ining the other fields in the valley a very much smaller number of 

 leafhoppers was found. Some fields had one individual to 10 beets, 



66— IV 



