172 HATCH EXPERIMENT STATTOX. [Jan. 



Part I. 

 REPORT ON FIELD EXPERIMENTS. 



CriAKI.ES A. GOESSMANN. 



1. Field Experiments carried on for the Purpose of 



STUDYING THE EfFECT OF A LiBERAL INTRODUCTION 



OF Clover-like Plants — Leguminous Crops — 

 INTO Farm Practice, as a Means of increasing 

 the Resources of Available Nitrogen Plant 

 Food in the Soil under Cultivation from the 

 Elementary Nitrogen of the Air. {Field A) 



The observation of the fact that the different varieties of 

 clover and of clover-like plants in general, as peas, beans, 

 vetches, lupines, etc., are in an exceptional degree qualified, 

 under favorable conditions, to convert, by the aid of certain 

 micro-organisms of the soil, the elementary nitrogen of the 

 air into plant food, imparts to that class of farm crops a 

 special interest from an economical stand-point. This cir- 

 cumstance is in a controlling degree due to the following 

 two causes : — 



First. — The nitrogen-containing soil constituents of plant 

 food are, as a rule, in a high degree liable to suffer serious 

 changes in regard to their character and fitness as well as in 

 reference to their quantity. 



Second. — Available nitrogen-furnishing manurial sub- 

 stances are the most costly articles of plant food in our 

 markets. 



Field experiments which propose to show, l)y their results, 

 to what extent the cultivation of clover-like plants can be 

 relied on as a practical and economical means for securing 

 efiiciently nitrogen plant food for the cro|),s to be raised have 



