294 AGRICULTURE OF MAINE. 



Many experiments have been made and many treatises have 

 been written showing the value of potash in agriculture. The 

 experimental data showing how crops can be grown without 

 potash are few. 



Recognizing the dearth of information and the prime im- 

 portance of the subject, the directors of the New England, New 

 Jersey and New York Experiment Stations held a special meet- 

 ing recently to discuss this subject and arrive at definite recom- 

 mendations for the crops for 1916. The paper which I present 

 today is based upon this discussion and the conclusions there 

 reached, supplemented by a few special ^tudies that have been 

 made by the Maine Agricultural Experiment Station, chiefly at 

 its Aroostook Farm. 



In the first place, there is no known substitute for potash in 

 agriculture, nor does any royal road, whereby the present crisis 

 due to the shortage and practical absence of potash salts from 

 the market may be overcome, exist. But there are certain ways 

 and conditions that can help tide over the present crisis. The 

 situation is, however, still farther complicated by the fact of an 

 advance in price of practically all kinds of plant food. Sulphu- 

 ric acid, which is essential to convert the insoluble phosphates 

 into available form, is in such a demand for the manufacture 

 of explosives that its price has been greatly augmented, thereby 

 increasing the cost of available phosp'horic acid. .Xitrates, 

 which are used in the manufacture of explosives as well as 

 being a fertilizer, come chiefly from the west coast of South 

 America. The deflection of enormous amounts of nitrates 

 because of tliis unusual activity in the manufacture of explo- 

 sives, coupled with the fact of the blocking of the Panama 

 Canal, has greatly increased the price of nitrate of soda and 

 reduced the amount that is actually available for agricultural 

 purposes in 191 6. 



Usually it has been practicable to get the supply of nitrate of 

 ■ oda by the long route around the Horn, and a few vessels are 

 now on the way from Chili. But the diversion of merchant 

 ' ips for war purposes has increased the cost of ocean trans- 

 j)ortation enormously. This is also acconnpanied by an actual 

 shortage of vessels sufficient to handle the world's commerce. 

 It is hoped that the Canal will be opened early in 1916, and it 

 may be that nitrate of soda can be abundantly purchased in 



