94 Maine Agricultural Experiment Station. 1920. 



or two per cent of potash and many none at all. Conditions 

 improved somewhat in 1917, there being more evidence of 3 and 

 4-per cent goods. A still greater proportion of the 1918 samples 

 were of the 4-per cent potash grade, while in 1919 some 6-per 

 cent goods were found. With the reduction in the amount of 

 potash used in potato fertilizers sold in Maine during the last 

 5 years there has been a tendency to increase the amount of 

 phosphoric acid, not because experience had indicated any need 

 for this, but apparently because it was the cheapest and most 

 plentiful fertilizing material that the manufacturers could ob- 

 tain. 



It is interesting to note that, in spite of these wide varia- 

 tions in the composition of the fertilizers used, no general com- 

 plaints have been made by the potato growers, previous to 1919, 

 of ill effects from their use, except where 5-10-0 or similar mix- 

 tures were used, although in 1918 there was some undercurrent 

 of feeling that the results obtained from goods carrying Ameri- 

 can potash were not quite up to expectations. While it is an 

 open question whether such excessive applications of potash as 

 are made when 2,000 pounds of fertilizer per acre are used, con- 

 taining 10 per cent of this material is necessary or wise, the re- 

 sults obtained from the practice previous to 1914 were such as to 

 convince many practical potato growers that it was good business. 

 The only bearing that the question has on the matter under con- 

 sideration is that it serves to emphasize the fact that even exces- 

 sive applications of the type of potash used prior to 1914 resulted 

 in no dissatisfaction on the part of the users. 



Field Observations ox Injured Potato Fields in 1919. 



Early in July 1919 rumors began to reach the Station that 

 some fields of potatoes in Aroostook County were not showing 

 normal germination and growth. Definite complaints began 

 to be received about the middle of July by both the State De- 

 partment of Agriculture and the Experiment Station. The 

 Director of the Station, and the Chiefs of the Bureaus of In- 

 spections and Seed Improvement of the State Department at 

 once decided to make a joint, personal investigation of the sit- 

 uation. As a member of this party the writer spent 10 days in 

 the field studying conditions at that time. During the remainder 



