14 CIRCULAR 16 8, U. S. DEPARTMENT OF AGRICULTURE 



The eggs are ovoid in shape, about QA millimeter in length, and 

 may be distinguished from those of C . sasakii by their light-yellow- 

 ish color and reticulate surface. The mature larvae are 6 millimeters 

 in length and flesh colored, with the head and plate of the first 

 thoracic segment brown. The cocoon is brown, 8 millimeters in 

 length, and of two layers, the outer of which is rough and open, 

 giving the cocoon a netted appearance. 



This and the preceding species are the most important pests in 

 Hokkaido, and the control measures used are designed to be effective 

 against both. Spraying for the codling moth in North America is 

 usually effective if done while the calyx cup is still open, as this is 

 the point of entrance of a majority of larvae, but such is not the case 

 with these two species. The best time for spraying has been found to 

 be between July 10 and 25, and stomach poisons are more effective 

 than contact sprays. The mixture known as Sapporo solution, which 

 is both a fungicide and an insecticide, has given the best results in 

 Hokkaido. This is a Bordeaux mixture containing approximately 

 6% pounds each of copper sulphate and of lime to 100 gallons of 

 water to which has been added 1 quart of stock solution of sodium 

 arsenite which is made by dissolving 1 pound of arsenious acid and 

 4 pounds of carbonate of soda in 1 gallon of water. 



The use of this spray is more satisfactory than bagging the fruit, 

 giving more complete control at lower cost and permitting better 

 coloring of the mature fruit. Also, less fruit drops prematurely from 

 the tree than when the bags are employed. Some growers are now 

 using lead arsenate in place of the above spray. At the present time 

 the cost of bagging is approximately 75 cents per 1,000 fruits, in 

 comparison with which spraying is much cheaper. The growers, 

 however, have a strong aversion to the use of any chemical sprays, 

 owing to the belief that an injurious amount of the poison is retained 

 upon the fruit when it is marketed, and a very large portion of them 

 still continue the use of bags. 



The fourth fruit feeder of importance is Nephoteryx pmvoreUa 

 (73, 90, 96, 11$), which causes extensive damage to pears throughout 

 Japan and Chosen. This species is frequently listed in literature as 

 N. rubizonella* but according to Matsumura this latter name is in- 

 correct. The injury by this species differs from that of those pre- 

 viously discussed in that the larvae do not feed exclusively upon the 

 fruit and that they attack it when it is small or half grown and leave 

 before it matures. According to Matsumoto (90) there are two 

 broods per year in the Okayama section of Honshu. The winter is 

 passed in the partly-grown larval stage within the buds, particularly 

 the flower buds. In the spring these larvae emerge and begin feed- 

 ing at the opening flower buds, which they cover with a web of silk, 

 thus preventing expansion. These larvae also bore into newly de- 

 veloped shoots, causing them to wilt and die, then move to others and 

 repeat the process. Later the young fruits are attacked, a single 

 larva binding a cluster of them together and feeding externally upon 

 all of them, usually where they touch one another. Maturity is 

 reached in the latter half of May. and pupation takes place in a 

 cavity made in the young fruit. After two weeks the adults emerge, 

 and the period of their greatest abundance is the first half of June. 

 Oviposition takes place soon after emergence, and the eggs hatch in 



