388 Bulletin 148. 



simply burrow back into the soil, however often they may be disturbed. 

 In 1897, one large infested quince orchard was plowed in January 

 to a depth of three or four inches ; the ground was bare and it froze 

 very soon after plowing. During the latter part of March and early 

 in April, this orchard was thoroughly cultivated, and the cultivation 

 continued later in the season. Yet, in spite of this, hundreds of the 

 quince curculios were captured on the trees in August. This cultiva- 

 tion cannot be depended upon to check this pest, while in its grub 

 stage in the soil, either in the fall or spring. 



Theoretically, however, thorough and rather deep cultivation at the 

 time the insect is passing through its tender pupa stage in the soil, 

 should destroy many of these pupae. Probably, during normal seasons, 

 the pupa stage is passed in the latter half of June or early in July. 

 We have no definite data as to the effect of deep, thorough cultivation 

 at this time or at this critical period in the life of the pest, except the 

 general statement of quince growers, who are considered good culti- 

 vators of their orchards, that they can see no effect from it upon the 

 numbers of the insect. 



Spraying. — Until within a few years, nearly everyone who has made 

 any serious attempt to control this pest, has used a poison spray for 

 this purpose. As a perusal of our story of its life will show, the 

 only stage of the pest that could be reached by a poison, is the cur- 

 culio or beetle ; the grub is inside the fruit, out of harm's way, from 

 the moment it hatches from the egg. The only chance to poison the 

 beetles is during the week or more which they spend in feeding on the 

 fruit, previous to and during the period of egg-laying. Although the 

 beetles are quite ravenous eaters, their method of feeding, as described 

 on page 382 and illustrated in figure 192, will at once show how little 

 chance there is to poison them. Most of their food they get from 

 beneath the skin in the flesh, only eating a minute hole through the 

 skin. 



Theoretically, then, the chances for poisoning the quince curculio 

 are small. Fortunately for the theory, it is the universal testimony of 

 quince growers who have thoroughly tested the arsenical sprays, 

 London purple and Paris green, against this pest, that they have been 

 able to see httle or no benefit from spraying. One large grower after 

 faithfully spraying with poison for several years without success, 

 became so discouraged as to seriously consider uprooting his trees. 



