8 Maine Agricultural Experiment Station. 1920 



within the endosperm occurring in flakelike groups with quite 

 definite margins, causing a more or less extending opaqueness. 

 This type was found to be very sensitive to environic conditions. 

 Both types were found to exhibit a distinctly different genetic 

 behavior controlled by different sets of genetic factors. The 

 practical importance of these results is apparent for they draw 

 a distinct line between true soft wheats like Sonora, Early Bart 

 which are not affected by climate and are every year 100% soft, 

 and the hard wheats whose response to environmental influences 

 manifests itself in a greater or less percentage of "yellow ber- 

 ries." 



The present paper deals with the results obtained in the 

 work with a number of pure lines of wheat originated and 

 grown at the Aroostook Farm of the Maine Agricultural Ex- 

 periment Station. The main object of this work was to attempt 

 to improve the strength of the Aroostook wheats, and this bul- 

 letin may be regarded in a way as a progress report on that 

 phase of this work based on the method of pure line selection. 

 In presenting the results of the chemical analyses the writer 

 wishes to emphasize the fact that these data reflecting as they 

 H.o the chemical composition and behavior of the wheats and 

 .lours, all refer to pure strains of wheat in distinction to com- 

 mercial varieties and flours. Some observations on the effect 

 of the environmental conditions of Northern Maine upon a few 

 pure strains of wheat introduced from Minnesota are also here 

 reported. 



Climate and Soil Relations in Aroostook County. 



As already stated the growing of wheat in Maine is con- 

 fined to its northern section made up chiefly of Aroostook 

 'County. In view of the exceptional significance commonly at- 

 tached to the environment in relation to the quality of wheat, a 

 Ibrief consideration of the climatic and soil factors of Northern 

 Maine appears desirable. 



Northern Maine is characterized by a cool, and moist cli- 

 mate and a short growing season. The mean temperature, the 

 -rainfall, and the number of clear days for the five months in 

 ■each of the last 7 seasons, 1913-1919, are given in Table 1. 



The outstanding feature in this table is the high precipita- 

 tion during the growing season. Reference to the data on cli- 



