I 

 THIRD ANNUAL REPORT OF STATE ENTOMOLOGIST. 209 



It is fortunate that the proper distance to set trees to get maxi- 

 mum returns in the crop is not less than the distance demanded in 

 order to conveniently and effectively spray. Thus, from both 

 standpoints it is clearly best not to set the trees so close that their 

 limbs can interlock. 



Prof. Fisher of the Horticultural Department of this college 

 recommends that in planting new orchards the trees be set not closer 

 than 25 to 30 feet. 



CLEAN CULTURE vs. COVER CROPS. 



In deciding whether to practice clean culture or to grow cover 

 crops the fruit grower may well bear in mind that much better re- 

 sults may be secured in fighting the codling moth in orchards in 

 which the ground is kept free of vegetation and can be stirred at 

 least during the time that larvae are seeking places for pupation. 

 It will be readily appreciated that the codling moth will find con- 

 ditions much less favorable in an orchard kept clean as in Plate IV 

 than in one in which legumes, grasses, or weeds are allowe-J to 

 grow. 



CARE OF THE FRUIT STORE-HOUSE. 



In harvesting fruit from an infested orchard many larvae will 

 be carried away with the fruit, for partly grown larvae may be in 

 apples that show no exterior sign. It follows then that man}" such 

 larvae will mature after being taken into the fruit houses an(! that 

 they will construct cocoons and mature the following spring, then 

 passing through windows and doors, will fly back to the trees. Dur- 

 ing the spring of the year when these moths are emerging they 

 should be prevented from leaving the fruit house either by keeping 

 the doors and windows closed or by attaching screens. These 

 facts should be borne in mind in constructing such store houses 

 and where possible each season the interior of the fruit house should 

 be thoroughly renovated during the winter or spring after the fruit 

 has been removed. Any moths that emerge from cocoons that 

 escape destruction during the renovation may be killed by hand or 

 by fumigation with potassium cyanide and sulphuric acid. 



At this point we should call attention to certain experiments 



