l8 MAIXE AGRICULTURAL EXPERIMENT STATION. 



plants was again sown in short rows and the process repeated 

 the next year. Over 12,000 plants have been grown in this way 

 in the four years. 



A careful analysis of this large amount of data has shown 

 that in these experiments selection within a pure line has not 

 permanently changed any of the characters studied. Thus plants 

 which have been subjected to three successive selections in the 

 plus direction do not on the average yield better than plants 

 which have been selected in the minus direction for three suc- 

 cessive years. 



The results of this work are of much importance to the prac- 

 tical oat breeder. It follows that in order to secure improved 

 strains it is only necessary to select individual plants from the 

 commercial fields and then to multiply the seed of each plant 

 separately. Then each of these pure lines must be tested and 

 only the best retained. After a desirable pure line has been 

 isolated it is only necessary to keep it pure and unmixed with 

 other seed. Such a pure line will not deteriorate nor can it be 

 improved by further selection. This greatly simplifies the meth- 

 ods of practical oat breeding. It is now shown that it is useless 

 to continue the expensiA'e methods of selecting year after year 

 within a pure line. In order to get still better yielding strains 

 it is necessary to go back to a commercial field and make new 

 selections with the hope of isolating still better pure lines. Once 

 a pure line is isolated it cannot be improved by further selection. 



The Blueberry Maggot the Same as Apple AIaggot. 



In the spring of 1913 the attention of the ]\laine Agricultural 

 Experiment Station was called to a certain maggot infesting 

 blueberries in Washington County. Although it was the opinion 

 of the growers that the berries afifected were winnowed out in the 

 process of sorting the berries, still their presejice caused con- 

 siderable concern, and in some localities it had become the prac- 

 tice to discontinue canning the fruit late in the season after the 

 maggot became abundant. 



Altogether it was a situation that warranted study both in 

 the economic interest of the blueberry industr}- and from the 

 entomological standpoint, for when the complaints first came in, 

 no one knew anything concerning the identity or habits of the 

 pest. 



