28 REPORT OF THE STATE ENTOMOLOGIST I92I 



is the most likely to be seriously infested and it appears probable 

 that a very considerable reduction in the numbers of the pest may 

 be secured in single brooded areas at least by concentrating efforts 

 upon the early corn. It should not be assumed that all the recom- 

 mendations given below are considered advisable for every infested 

 area. It is believed that a recognition of the factors involved and 

 judicious application of the recommendations to local conditions 

 may result most beneficially. 



1 Cut corn close to the ground, since many of the borers winter 

 in the stubble. 



2 Put as much of the corn into silos as possible because the borers 

 are killed by the fermentation of the ensilage. This also applies to 

 waste from canning factories. 



3 Cut or shred corn stalks fed to cattle in order to promote 

 their consumption. In any event keep the uneaten parts, the 

 " orts," out of the manure and provide for the destruction by Ma)' 

 15th of the contained borers in all such materials whether in field, 

 lot or barn, by burning, plowing under or submerging in water for 

 some 40 days, unless the stalks are worked into piles containing 

 considerable horse manure which will heat to such an extent as to 

 destroy the borers. 



4 Fall plowing, especially early and thorough, destroys many 

 borers. It is considered advisable to encourage the practice in the 

 infested areas. Heavy rolling prior to plowing has been suggested 

 as a valuable aid, because many borers are killed by crushing the 

 butts and it is then easier to turn the stubble under. 



5 Weeds and other plants growing in or near badly infested corn 

 may be invaded by borers in late August or September ; conse- 

 quently clean culture is of service in reducing the number of stems 

 in which the pests may winter. Burning over in late fall or early 

 spring of waste or weedy areas in or adjacent to corn fields, 

 especially badly infested ones, is advised. 



6 Corn stalks, cobs and almost any thick part of all herbaceous 

 plants may contain these borers under certain conditions and their 

 shipment or removal from the infested area is dangerous and in 

 many cases a violation of quarantine regulations. 



7 Crops particularly likely to carry the borer, such as celery, 

 beets, dahlias etc., should not be grown in the infested areas within 

 50 feet of corn because the borers, deserting the corn for one reason 

 or another, may crawl 30 feet or more before entering some other 

 Dlant. 



