182 MASSACHUSETTS HORTICULTURAL SOCIETY. 



The adoption of this course of manuring our lands has not only 

 materially improved our chances of securing larger crops, but, 

 what is of not less importance, it has enabled us to notice the 

 particular intluences which the different essential articles of plant 

 food not unfrequently exert on the quality of the crop. Observa- 

 tions in this direction are today so well established that no one 

 familiar with the facts can reasonably question their important 

 bearing on vital interests in agricultural and horticultural indus- 

 tries. 



We have good reason to believe that not only the particular 

 form, but also the particular association and relative proportion, 

 in which we apply the various articles of plant food, will, under 

 corresponding conditions of season and soil, control in many in- 

 stances the special commercial value of our crops. 



We begin to discriminate between muriate of potash and sul- 

 phate of potash ; we learn that a liberal supply of nitrogen and 

 potash, in the absence of a corresponding proportion of phos- 

 phoric acid, tends to retard the timely maturing of some crops ; it 

 is not less recognized that sulphate of lime and sulphate of mag- 

 nesia (kieserite) favor in an exceptional degree the growth of 

 leaves and stems ; sulphate of magnesia (kieserite) used in con- 

 nection with potash compounds is known to send the potash to the 

 subsoil and has thus proved a most efficient remedy for clover and 

 beet sick lauds ; and the same effect may be expected in our 

 orchards, as far as distribution of potash is concerned. 



More observations of a similar character might be mentioned 

 in this connection, yet I cannot attempt, on an occasion like the 

 present, an exhaustive treatment of the matter under discussion. 

 1 take the liberty to call your serious attention to the previous 

 statements merely on account of their suggestive importance. 



To be able to produce in some plants, or in a particular part of 

 any plant, an exceptionally large amount of sugar, or starch, or 

 acid, or nitrogenous matter ; in others to cause an exceptional de- 

 velopment of leaves and stems ; and again in others to exert a 

 decided influence on the length of time required to reach their full 

 maturity means in the end nothing less than that our chances for 

 controlling the quality of our crops are daily improving. The re- 

 sults thus far known are of sufficient importance to incite us to 

 active participation in a systematic course of experimental obser- 

 vation, b}' which we may hope to make further progress in a 

 rational system of special fertilization. 



