A STUDY OF FACTORS INFLUENCING THE YIELD OF POTATOES 1273 



of the influence of certain factors on yield. A larger number of records 

 for each region, and replication of the survey, may be suggested as the 

 best and probably the only means of obviating these conditions. Whereas 

 sufficient records were not available for the detailed study of some factors, 

 the number used has, on the whole, afforded means for fairly definite 

 conclusions. For as extensive a study of details as has been pursued in 

 the present investigations, not less than three hundred, and preferably 

 four hundred, records should be used. Aside from the relative influence 

 of various factors on yield as revealed in these studies, it has been possible 

 to correct, as well as to verify, many popular ideas of long standing. Altho 

 the " what," the " why," and the " how " of crop production have for 

 years been projected to the farmer, the regional study of actual cause 

 and effect by survey methods has at least contributed to the knowledge 

 as to the " how much." 



AUTHOR'S ACKNOWLEDGMENT 



The writer wishes to make acknowledgment of the help given him by 

 Professor E. G. Montgomery, under whose direction this investigation 

 was made, and to express appreciation to Messrs. D. S. Fox, W. M. 

 Peacock, M. F. Abell, R. F. Pollard, and R. H. Cross, who assisted in the 

 taking of records. Grateful acknowledgment is made also to the many 

 farmers who furnished the information necessary, and to Miss Nellie Van 

 Dyne for her capable assistance in the compilation of the data. 



