EXPERIMENT STATION BULLETINS. 335 



WHEN THE CODLING-MOTH FLIES. 



While the first week in August is a good average time for applying an 

 arsenical spray for the second generation of the Codling-moth in Michi- 

 gan, it is well to remember that seasons vary, and that the time set aims 

 merely at an average. To determine exactly each year just when to get 

 the highest efficiency out of a spray, for a particular locality, requires 

 only a few hours of work, providing one can find some neglected apple 

 trees near at hand. 



First of all scrape off all loose bark-flakes from the trunk and limbs 

 of several trees, thus destroying all the natural places for the hiding 

 away of the cocoons. The scraping is most easily done while the bark 

 is soft after a prolonged rain. 



Next, make some bands of burlaps six or eight inches broad and three 

 or four layers thick ; place one around the trunk of each prepared tree 

 and fasten with a headless wire nail driven into the tree so that the 

 band can easily be removed. Do this in June so that the cloth may be- 

 come weathered before the time for spinning up. The larvae in searching 

 for a good place to spin cocoons will find the bands, in the absence of 

 other protection, and spin cocoons there. 



Occasionally examinations during July will reveal these cocoons 

 which should be carefully removed by cutting out a small bit of the cloth 

 to which each is fastened. 



Place all these bits of cloth with the cocoons attached in a cage made 

 of a lantern globe or some other glass cylinder open at top and bottom, 

 and then tie a bit of mosquito netting over the top to confine the insects 

 when they come out of the cocoons. If the lantern globe is set on a 

 little soil in a flower pot and the soil is kept just slightly moist, the 

 chances of getting the moths out are increased. 



Now put the cage thus prepared in a shady place where the sun can- 

 not strike it to sweat it, and where the rain cannot penetrate. Outside 

 of protection from rain and sun the conditions should be as near those of 

 the outside as possible. Keep the soil in the pot just moist and look 

 for the moths often during late July for they will hide down under the 

 layers of burlaps and may be overlooked. When you see them in the 

 cage, then you know that they are laying eggs in the orchard and the 

 time to spray is just before the young hatch and go into the fruit, not 

 afterward. Of course they do not come out all together but string along 

 over quite a period. 



