108 HATCH EXPERIxMENT STATION. [Jan. 



his selection with due care. An intelligent selection of fer- 

 tilizers from among the various brands offered for sale 

 requires, in the main, two kinds of knowledge ; namely, 

 that the brand of fertilizer in question actually contains the 

 guaranteed quantities and qualities of essential articles of 

 plant food at a reasonable cost, and that it contains them in 

 such form and proportions as will best meet under existing 

 circumstances the special wants of soil and crop. 



As the physical conditions and chemical resources of soils 

 in available plant food frequently difter widely even on the 

 same farm, no definite rule can be given for manuring farm 

 lands, beyond the advice to return to the soil in available 

 form those plant constituents which the crops raised in pre- 

 ceding years have abstracted in exceptionally large propor- 

 tion, and which will be especially called for by the crops to 

 be raised. 



To assist farmers in selecting their fertilizers with refer- 

 ence to the wants of the crops they wish to cultivate, the 

 writer has for years published in his annual reports a com- 

 pilation of the analyses of farm and garden crops, to serve 

 as a guide to all interested in a rational mode of manuring 

 plants. Copies of these compilations of analyses may be 

 secured by asking for them at the office of the Hatch Ex- 

 periment Station, at Amherst, Mass. 



In making choice from among the so-called complete fertil- 

 izers, two points in particular seem to be worth rememl)ering. 

 First, select them with reference to the amount, the quality 

 and the kind of essential constituents they are guaranteed 

 to contain, and not merely with reference to the cost per 

 ton ; mere trade names are no giiaraiitee of fitness. High- 

 priced articles, when offered by reputable manufticturers, 

 have proved in many instances cheaper than low-priced 

 goods. Second, hnj your supplies of reputa])lc dealers, 

 and insist in all cases on a statement of guaranteed com- 

 position. 



Valuation of Commercial Fertilizers. 



The market value of the higher grades of agricultural 

 chemicals and compound feitilizers depends in the ma- 

 jority of cases on the amount and the particular form of 



