MISCKIJ.ANEOL'S NOTES ON ECONOMIC WORK 63 



At present we can suggest only general methods of control, 

 such as. — ■ 



1. Stacking' the grain and threshing from the stack. This 

 would preA'ent the escape of all the flies, which naturally emerge in 

 the fall, except those emerging from the outer layers of the stack. 



2. Trap crops may be used to attract the insect and later de- 

 stroyed. 



3. Plowing under volunteer grain after harvest and keeping- 

 wild grasess in check by clean cultivation. 



Where fall wheat is sown, the sowing should be done as late 

 as possible in the fall, which is also a good control measure for 

 Hessian fly. 



Small Fruit Insects. ='= 



Two important insects of small fruits studied have been the 

 Strawberry Weevil and the Raspberry fruit worm. 



The Strawberry A\'eevil damages the blossoms and prevents 

 the formation of fruit. The insect itself is very small, only about 

 1-10 of an inch in length, yet is capable of destroying 20 to 90% of 

 the Inids in a strawberry held. We have found that in Minnesota 

 the weevils hibernate entirely within the strawberry field under the 

 straw and leaves in the old bed. When the plants blossom in the 

 spring the insects are present ready to do the damage. 



Control. Old beds serve as excellent breeding places for these 

 insects and hence when the weevils are present the one-crop system 

 is recommended. If two crops are to be obtained, the field should 

 be thoroughly cleaned of weeds after the fruit harvest and the bed 

 should be burned o\er. In other words, make a new bed after every 

 harvest. Spraying as recommended by other experimental stations 

 has given poor results in Minnesota. 



The Raspberry fruit worm is recognized as the small, brownish 

 white worm that one often finds clinging to the core of the berry. 

 Berries infested with this grub are smaller and discolored, and make 

 necessary the picking over of all raspberries intended for the table. 

 The weevils pass the winter as pupae in the soil near the base of 

 the plants. In the spring when the young plants are about six 

 inches high the insects leave the ground as beetles and feed on the 

 tender leaves and buds. Often 10 to 15 per cent are thus injured. 

 The King and the Miller varieties are most severely attacked, while 

 Cuthberts and Black Caps are more or less immune. 



*Mr. Simon Marcovitch has done the investigational work with these and with weed in- 

 sects. 



