108 HATCH EXPERIMENT STATION. [Jan. 



Number with two elements below the lowest guarantee, ... 6 

 Number with one element below the lowest guarantee, , . .29 



(b) Where two essential elements of plant feed were guaran- 



teed : — 

 Number with two elements above the highest guarantee, . . 3 

 Number with one element above the highest guarantee, . . .10 

 Number with two elements between the lowest and highest guaran- 

 tees, 13 



Number with one element between the lowest and highest guaran- 

 tees, 12 



Number with one element below the lowest guarantee, ... 6 

 Number with two elements below the lowest guarantee, ... 3 



(c) Where one essential element of plant food was guaran- 



teed : — 



Number above the highest guarantee, 10 



Number between the lowest and highest guarantees, . . .23 

 Number below the lowest guarantee, 1 



The modes of analyses adopted in this work were in all 

 essential points those recommended by the Association of 

 Official Chemists. 



Attention has been called, in previous reports, to the fact 

 that the introduction of a more liberal amount of potash into 

 the make-up of a large class of so-called complete manures 

 has become from year to year more general. This change 

 has been slow but decided, and in a large degree may be 

 ascribed to the daily increasing evidence, resulting from 

 actual observations in field and garden, that the farm lands 

 of Massachusetts are frequently especially deficient in potash 

 compounds, and consequently need in many instances a more 

 liberal supply of available potash from outside sources to 

 give satisfactory returns. Whenever garden vegetables, fruits 

 and forage crops constitute the principal products of the 

 land, this recent change in the mode of manuring deserves a 

 particularly careful trial ; for the crops raised consume ex- 

 ceptionally large quantities of potash, as compared with grain 

 crops. In view of these facts, it will be conceded that a 

 system of manuring farm and garden which tends to meet 

 the more satisfactory recognized conditions of large areas 

 of land, as well as the special wants of important growing 

 branches of agricultural industries, is a movement in the 

 right direction. 



In repeating these statements, it is not assumed that it will 



