406 EXPERIMENT STATION RECORD. 



"Screens placed over the windows and doors of the cellar or rooms where apples 

 have heen stored will prevent those larvae which are taken in with the apples from 

 escaping as moths in the spring.'' 



The Orthoptera of Minnesota, O. Lugger (Minnesota Sta. Bui. 55, 

 pp. i> 1-386, figs. 188). — The bulletin gives the distribution, structure, 

 and habits of the more destructive species of locusts, with methods of 

 combating them; remedies for cockroaches and other ortbopterous 

 insects; an account of the parasites and other natural enemies of locusts; 

 a description of the external anatomy of the two-striped locust (Melon- 

 oplusbiviitotus) ; an account of the internal structure and metamorphosis 

 of locusts; and a classification and technical description of the species 

 of Orthoptera occurring in Minnesota. 



In regard to remedies against locusts the author says: 



"The true remedy consists in plowing, and wherever locusts are numerous this 

 method has to he employed. Plow tbe soil containing the eggs during the autumn, 

 if possible, as by doing so the surface of the plowed ground becomes thoroughly com- 

 pact by wind, rain, and snow. Plowing in spring, if well done, and as early as pos- 

 sible, will also be successful, though in s >me cases, and especially in a dry season, a 

 few locusts may succeed in reaching the surface." 



To determine whether young locusts can reach the surface in plowed 

 ground, eggs of Melanoplus spretus and M. atlanis were planted at dif- 

 ferent depths in flower pots containing soil similar to that from which 

 the eggs had been removed. In one lot the soil was moistened occa- 

 sionally and in the other kept dry. The results are shown in the 

 following table: 



Percentage of locusts reaching surface of soil with e/jgs placed at different depths. 



Depths at which eggs were placed. 



Soil kept 

 dry. 



Soil 

 moist- 

 ened. 



One inch..:.. 

 Two indies . . 

 Three inches. 

 Four inches. . 

 Five inches.. 

 Six inches . . . 



Per cent. 

 !I3 

 86 

 51 

 13 

 2 

 



Per cent. 



87 



43 



11 



1 











Where locusts are not numerous enough to warrant plowing, burning 

 the grass may be useful. Where eggs are deposited in large numbers 

 in restricted areas, much good may be done by collecting and destroy- 

 ing them. To do this, especially where the soil is light, about an inch of 

 the surface soil is removed and the eggs sifted out and buried. In 

 case it is impracticable to plow, as in meadows and pastures, much 

 good may be accomplished by poisoning the edges of adjoining grain 

 fields. Locusts may also be poisoned in gardens by using poison bran 

 mash as a bait. Hopperdozers are considered very useful in destroy- 

 ing locusts, but are "only a makeshift, to be employed when better 

 remedies can no longer be used." 



