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IMMUNITY OF SOUTHERN DAKOTA FROM THE CHINCH BUG. 



Our old time friend and correspondent, IVIr. W. W. Corbett, of Fargo, 

 wrote us recently concerning- tUe possibilitj' or probability of the ap- 

 pearance of the Chinch Bag in destructive numbers in Dakota. The 

 subject is one of general interest and we copy at length from our reply : 



The question which you ask iu yours of the 25th ultiiiio is uot one which admits 

 of a thoroughly satisfactory auswei'. I have thought sometimes that tliere was dan- 

 ger ahead for the wheat crops of southern Dakota from the Chinch Bug, and I have 

 expected to hear of damage from it. The immunity so far experienced is doubtless 

 due to the fact that the Chinch 15ug is essentially a southern insect, occurring in its 

 greatest abundance in portions of the country where the winters are not so severe 

 as they are with you. Occasionally, however, they do some damage as far north as 

 Wisconsin and even parts of southern Minnesota, and I should not be surprised at any 

 time to learn that a race of the species had established itself iu these more northern 

 sections and had adapted itself to the more severe^ cold of your winters. Such an 

 occurrence may, however, be indefinitely postponed. From my experience I would 

 say that your blizzards will prove a great protection against it, but at the same time 

 I would keep on the look-out, and if I had large wheat interests in your vicinity, 

 and were uot an entomologist, I would not fail to post myself upon the habits of this 

 insect and watch for it constantly. Another cause of your immunity up to the pres- 

 ent time, I think, may be found in the common practice of burniug the prairies iu 

 autumn in the country that is perfectly new, for this custom has the eft'ect of destroy- 

 ing the bulk of the Chinch Bugs that otherwise would hibernate, and upon these 

 grounds you may expect iu the more southern part of your Territory that the insect 

 may become more numerous in proportion as the country is settled up and fenced 

 and prairie tires are prevented. 



BURNING THE STUBBLE FOR HESSIAN FLIES. 



Mr. Fred Enock and ]Miss Ormerod have carried on a spirited discus 

 siou iu the columns of the Mark Lane Express, of London, on the advisa- 

 bility of burning the stubble as a remedy against the Hessian Fly. Mr. 

 Enock holds that it is bad policy for the reason that the parasites of the 

 pest are thus destroyed along with the unparasitized pui)aiia. He ad- 

 vocates an extensive rearing of parasites, and an endeavor to cultivate 

 them artificially in order to liberate them afterward in the fields. Miss 

 Ormerod takes quite the contrary view, and holds that burniug of the 

 stubble regardless of parasites is the better plan. We had occasion dur- 

 ing January to write Mr. Enock upon this subject, and quote from our 

 letter as follows : 



* * * The question under discussion is an old one, and oue which will probably 

 never be settled to every one's satisfaction. Theoretically you are right, and practi- 

 cally Miss Ormerod is right. At present, and with general entomological knowledge 

 .u its present state, there can be no doubt that it will be advisable to burn or other- 

 wise destroy screenings which examination shows to contain puparia. It is a great 

 bother for any one to try to breed parasites, and for a practical man it is out of the 

 question. The burning of stubble is something which depends entirely upon local 

 conditions. * » * There are cases when the consideration of the parasites has an 

 immense practical bearing, but with the Hessian Fly in Englaud to-day I am inclined 

 to believe tliat the study of the parasites is of value only as indicating the origin of 

 the pest and, by observation of their m mbors, as a means of prediction during a 



