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occasions upon pear trees and which has in a few instances killed plum 

 trees on the western slope. 



The brown mite, Bryohia pratensis^ occurs in myriads in orchards 

 in the western portion of the State. As early as May 20 of this year 

 the foliage of many pear, apple, and plum trees was showing very dis- 

 tinctly the bleaching effect of the attack of these mites. In the winter 

 time there are portions of the trunk and limbs of the trees that are 

 colored red with myriads of eggs that are to hatch the spring brood. 

 The eggs are readily destroyed by strong applications of kerosene 

 emulsion or h\ the lime, salt, and sulphur mixture, and the ordinary 

 kerosene emulsion destroys the mites after they hatch. 



Some farm and garden pests are as abundant in Colorado as anywhere, 

 and among these are the imported cabbage butterfly, Pieris rapm, 

 the cabbage louse, Aphis ht'cisslcce, the cabbage Plutella, P. crucifera- 

 Tum^ the pea weevil, the squash bug, the onion thrips, and cutworms. 

 In addition we have the bean beetle, very destructive to wax beans, 

 and other enemies of less importance. 



The beet arm}'' worm, LapTiygma flavimaculata, made a very inter- 

 esting record for itself last year in localities in the State where sugar 

 beets were grown. I can not find that the insect has ever been reported 

 as an injurious species before. 



Specimens sent to Prof. J. B. Smith were named for me as above, 

 and I afterwards found that there were specimens of the moth in the 

 collection that had been taken at night at Denver and at Boulder. 



My attention was first called to the insect as a beet enemy by Mr. 

 C. E. Mitchell, with the Colorado Sugar Manufacturing Company, 

 Grand Junction, Colo. Mr. Mitchell first wrote to another person, 

 about the 20th of July (the letter nev^er coming into my hands), stating 

 that a worm had appeared in considerable numbers upon beets in por- 

 tions of Grand Valley. On July 29 Mr. Mitchell wrote, saying: "The 

 worms have disappeared almost entirely during the past week. They 

 seem to have gone into the ground." On the 12th of August a tele- 

 gram was received from Mr. Mitchell stating that the worms had again 

 appeared, and asking me to go at once to investigate the matter. 

 This I did. The caterpillars were scattered to some extent over the 

 entire area planted to beets, but the chief injuries were upon newly 

 broken ground between Grand Junction and Palisades. Not less than 

 200 acres of beets had their leaves badly stripped, and fully half this 

 acreage was so badly eaten down that the crop was not worth harvest- 

 ing. When the beet leaves were devoured, the caterpillars ate in just 

 beneath the crown and then went down on the beet. In fields where 

 the beet leaves were mostly eaten away, the caterpillars were crawling 

 over the ground in all directions in search of food, and thc}^ seemed 

 to be able to make use of almost ain" green thing for this purpose. 

 Potatoes in some cases suffered badly .^ as did small fruit trees where 



