THE STRAW r.KRin- WEEVIL IN MINNESOTA 125 



The two-crop system. — Hie one-crop system does nut appeal 

 to many of the farmers wlio lia\e been accustomed to two or more 

 crops from the same bed. Much of the injury from the weevils 

 can be avoided even where the two-crop system is practiced by 

 thoroughly burning- over and renewing the bed. As soon after 

 picking- as possible, the beds should be mowed, and when dried out, 

 a thin layer of straw should be spread over the bed and the patch 

 l)urned over. After this operation, the beds ought to be Vi'ell culti- 

 vated all over and the rows narrowed to about one foot. The aim 

 should be to make the bed as clean as a new field. All the dead 

 leaves, weeds, and other rubbish, all of which make suitable hiber- 

 nating" quarters for the adults, will thus be removed. Under field 

 conditions, it was difficult to find a single weevil where the beds 

 were burned over and cultivated. Wilkinson remarks that burning 

 over is advantageous for the following reasons : 



1. The bed is left clean; 



2. The insects and diseases are killed or controlled ; 



3. The lied, being clean, is easier to work. 



More than two crops ought never to be taken from the same 

 field, and old neglected patches should not be tolerated, since they 

 serve as breeding grounds. 



Summary. 



1. In Minnesota, the adult weevils make their appearance the 

 latter part of April or early in May, feeding on the under side of 

 the leaves until the pollen is mature. 



2. The buds are first cut as soon as the first blossom shows 

 and the fruit pedicels are about two inches high. 



3. Fields with from 40 to 95 per cent of the buds cut were 

 not uncommon. 



4. The new brood emerges soon after picking, eating small 

 holes on the under side of leaves. 



5. Hibernation began the latter part of August, in 1915, among 

 the dead leaves in the strawberry patch. 



6. The weevils pass the winter in the strawberry beds and not 

 in the woods, at least in Minnesota. 



7. Old beds are more severely infested than younger ones. 



8. The natural enemies reared were five species of Chalcids 

 and one Cecidomyid. 



9. The indications are that the weevils are not able to emerge 

 when plowed under or covered with soil during cultivation. 



