154 EXPERIMENT STATION RECORD. [Vol. 30 



that the yield of corn, wheat, and oats in these infested counties was dimin- 

 ished by chinch bug infestation in the year 1914 as follows: Corn, $5,015,874; 

 wheat, $1,356,039; oats, $41,071— a total of $6,442,984. . . . 



"An analysis of the weather and other conditions for several years in the 

 region where the chinch bug outbreak began, points to a conclusion that the 

 immediate cause of its beginning was unusually hot midsummer weather, with 

 no excessive rainfall, occurring in a region in w^hich the food plants occu- 

 pied a relatively large area, with winter wheat in especially large ratio. . . . 

 The outbreak was brought to a conclusion in the spring and early summer of 

 1915 by heavy beating and flooding rains coming at times when the young bugs 

 were hatching rapidly from the egg. 



" The principal measures for the control of a chinch bug outbreak are the 

 burning out of the insects in their winter quarters and their destruction at 

 harvest time by means of impassable barriers and lines of post-hole traps 

 placed beside infested fields of wheat. Although winter burning on a large 

 scale proved impracticable in Illinois owing to wet and snovry winters, small 

 scale field experiments with this operation, under conditions locally and tem- 

 porarily favorable, destroyed from 50 to 75 per cent of the chinch bugs under 

 the harborage burned over." 



Experiments made with a view to finding a better material than coal tar 

 for making barriers against the escape of chinch bugs at wheat harvest re- 

 sulted in the selection of a petroleum product, a residue of distillation, con- 

 taining 70 per cent of asphaltic materials and known as road oil No. 7. While 

 a perfect substance for the purpose this material, however, has the disad- 

 vantage that it is not on the market and must be made solely for this special 

 use. A farmer's chance experiment made in 1912 showed that crude creosote 

 was almost as effective as coal tar or road oils, and it had the advantage that 

 it could always be obtained without delay in any desired quantity from near-by 

 sources of supply, and so was the substance principally used during the last 

 year or two of the outbreak. Experiments showed that creosote differed from 

 coal tar and the road oils in the cause of its effectiveness, the latter being im- 

 passable because they were thick and sticky, while the creosote repelled the 

 insects by odorous vapors given off. 



" Field experiments with practical operations, especially in 1910, 1911, and 

 1912, showed that an effective barrier could be made and maintained at an ex- 

 pense for labor and materials varying from $1.50 to $2 per day per mile, the 

 difference depending mainly upon the character of the season." 



The false chinch bug and measures for controlling it, F. B. Milliken 

 (U. S. Dcpt. Agr., Farmers' Bui. 762 {1916), pp. 4, figs. 2). — A severe outbreak 

 of the false chinch bug (Nysius ericce [angiiHtatnsI) during May and June, 1916, 

 especially in Kansas and Colorado, led to the preparation of this information 

 regarding control measures. 



Are scales becoming resistant to fumigation? H. J. Qitayle (Univ. Cal. 

 Jour. Agr., 3 {1916), No. 8, pp. 333, 33Jt, 558).— The author discusses fumigation 

 experiments with fruit from different sections showing apparently that the 

 red scale in the Corona district is more resistant than in Orange County. 



Root louse control, D. Hansen {V. S. Dept. Agr., Bnr. Plant Indus., Work 

 nuntleij Expt. Farm, 1915, pp. 16-18). — Experimental control work with the 

 sugar beet root louse {Pemphigus hetw), accounts of which by Parker have 

 been previously noted (E. S. R., 33, p. 357), was carried on In cooperation 

 with the Montana Experiment Station. 



Due to an unusually heavy rainfall in June and July the soil on all the 

 plats was thoroughly moist most of the time during the migration period and 



