FIGHTING THE APPLE WORM 481 



increase from the first to the last is enormous. The worms escaping 

 from the fruit in the fall hibernate as larvae under the loose bark of 

 the tree, or in store-houses, or in any available dry place. 



On the basis of long experience in the Watsonville district Mr. 

 W. H. Volck, county entomologist, gives the following outline of opera- 

 tions against the apple worm : 



There are two broods in a season. The first develops from worms that have 

 wintered over in protected places both above and in the ground. The moths 

 of the first generation begin emerging in April, but very few eggs are laid before 

 the middle of May. In this locality, egg-laying is then continuous until the last 

 of June. 



The full-grown worms of the first generation after emerging from the apples 

 seek some hiding place where they may rest for a few days, transforming into 

 pupa and then into full-grown moths. 



The moths of the second generation begin laying eggs early in August and 

 may continue to do so as late as October or November. It is the worms of the 

 second generation that do the greatest amount of damage. 



The codlin moth lays its eggs on the surface of the leaves and fruit. The 

 eggs are about the size of a small pin-head, circular and flat. The color varies 

 from white to pink and red. These eggs are easily seen when the observer 

 knows what to look for. 



The young worms hatch from the eggs about ten days after laying, and 

 then begin crawling about in search of fruit to burrow into. This short period 

 between the hatching of the egg and the entrance into the apple is the only 

 time that spraying operations can prove effective. It is clearly impossible to 

 accomplish anything by the use of sprays that will only kill by contact, for such 

 sprays would have to be applied nearly every day. The spraying operation must 

 then leave a deposit of some substance on the fruit that will kill the worms 

 when they attempt to burrow through the rind. The only substance now 

 known that answers these requirements are the compounds of arsenic. 



Arsenic is, however, poisonous to plants and must be applied with caution. 

 The arsenic compound used must be entirely insoluble in water, and not subject 

 to weathering, in order that it shall be perfectly safe. The wet fogs of the 

 Pajaro valley summers give arsenical spray compounds a very severe test, and 

 it has been found that only the best quality of arsenate of lead is able to stand it. 

 Arsenate of lead may do very severe burning, however, if it is not of the 

 proper quality. 



It is a well-known fact that a large percentage of the worms of the first 

 generation enter at the blossom ends of the apples. This part is protected or 

 more or less closed over by the leaves of the calyx. 



The calyx cups close very shortly after the petals fall, and so it is advised 

 by the best authorities to spray as soon after the falling of the blossoms as 

 possible in order to leave a deposit of poison there. In the Pajaro valley and 

 adjoining sections, weather conditions often prevent spraying at this time, but 

 where possible to apply, the calyx cup spraying is advised. 



Good results have been obtained by spraying in the early part of May, 

 which is considerably after the calyx cups have closed. Spraying at this time 

 gives much the same effect as the calyx cup application, especially where it is 

 applied with proper thoroughness. This early spraying is applied before any 

 worms have appeared and is intended merely to have the poison in readiness 

 for the insects when they do come. 



The first codlin moth spraying should contain Bordeaux Mixture as a pre- 

 caution against the scab: 



Bordeaux Mixture Copper sulphate 3 pounds, lime 4 pounds, water 50 

 gallons. 



Arsenate of Lead Use 2 l / 2 to 3 pounds of arsenate of lead to each 50 gallons 

 of Bordeaux. 



The Bordeaux Mixture should be prepared first, and enough space left in 

 the tank to allow for the addition of the arsenate of lead and the water required 

 to mix it. 



