-5- 



Life History. The oyster shell scale spends the winter in the egg 

 stage, concealed under the protection of the old scale cover. In the spring, 

 soon after petal fall, the eggs begin to hatch, and hatching continues over 

 a period of ten days or more. The newly-hatched scale is a ninute, active, 

 crawler with six legs. The crawler soon settles down, inserts its sucking 

 tube into the apple bark, and begins to form its protective scale cover. 

 After the scale insect forms its protective cover, it sheds its legs, and 

 never moves from that spot. The scale grov.'s in size until late summer, vifhen 

 it reaches full size, and eggs are soon formed. After the eggs have been 

 deposited, the parent insect under the scale shrivels away and- dies. Each 

 scale may deposit from 50 to 100 or more eggs. 



Control Pr oblems. The present infestation of oyster shell scale is 

 most severe in well-cared-for orchards, and especially in orchards which 

 have been consistently dusted. It has been observed that neglected trees 

 may be practically free from scales, while adjoining v^'ell-treated commercial 

 orchards are severely infested. This suggests that the spray or dust in 

 some way favors the development of the scales. Perhaps the sulphur destroys 

 many of the natural enemies which othoi'v.'ise v;ould 1<e ep the scales under con- 

 trol. 



The thorough application of dinitro-oil spray in the early 

 spring, while the apple buds are still dormant, has given satisfactory con- 

 trol of oyster shell scale. There are some valid objections to this treat- 

 ment, however. First, very thorough coverage is required, vriiich is expen- 

 sive of time, material, and labor. In Maine there is only a very short 

 period between the passing of the snow cover and the beginning of activity 

 of the apple buds. Moreover, it usually is very difficult to drive a 

 sprayer through our orchards during that period. 



There is need for an effective spring or sui.Tmer treatment, 

 perhaps directed at the destruction of the nev/ly-hatched scales. Preliminary 

 experiments have not yet developed such a treatment that fully meets the 

 requirements of the Maine apple growers, 



— F. H. Lathrop, Entomologist 

 Maine Agricultural Experiment Station 



APPLE MARKET REPORTS 



By this time most growers in Massachusetts vdll have received 

 notice that the Apple Market Reports issued by this Department will again be 

 available this season. Definite decision to r esume the service, despite the 

 short crop, has been made upon receipt of a request representing the unanimous 

 vote of the Executive Committee of the Massachusetts Fruit Growers' Associa- 

 tion, 



At first thought the combination of a very light crop, to- 

 gether with price control, might make it appear that apple quotations would 

 be subject to very little change this season. Hov/ever, sales of early apples 



