22 TALKS ON MANURES. 



and in the best manner. No weeds choke the wheat plants or rob 

 them of their food ; but that field does not produce as much wheat 

 by 30 bushels per acre as the season is capable of producing. 

 WhyV The answer is evident. Because the wheat plants do not 

 find food enough in the soil. Now, anything that will furnish 

 this food, anything that will cause thai field to produce what the 

 climate or season is capable of producing, is manure. A gardener 

 may increase his crops by artificial heat, or by an increased supply 

 of water, but this is not manure. The effect is due to improved 

 climatic conditions. It has nothin;^ to do with the queslioa of 

 manure. We often read in the agricultural papers about ' s/utdc 

 as manure.' We might just as well talk al)oul sunlight as ' ma- 

 nure.' The effects observed shouhl be referred U> modifications of 

 the climate or season; an.l so in regard to mulching. A good 

 mulch may often produce a larger increase of growth than an ap- 

 plication of manure. But mulch, proper, is not manure. It is 

 climate. It cheeks evaporation of moisture from the soil. We 

 might as well speak of rain as manure as to call a mulch manure. 

 In fact, an ordinary shower in summer Ls little more than a mulch. 

 It does not reach the roots of plants ; and yet we see the effect 

 of the shower immediately ia the increased vigor of the plants. 

 They are full of sap, and t'.ic drooping leaves look refreshed. We 

 say the rain has revived them, and so it has ; but probably not a 

 particle of the rain has entered into the circulation of the plant. 

 The rain checked evaporation from the soil and from the leaves. 

 A cool night refreshes the plants, and fills the leaves with sap, pre- 

 cisely in the same way. All these fertilizing cflFects, however, 

 behmg to climate. It is inaccurate to associate either mulching, 

 sunshine, shade, heat, dews, or rain, with tlie question of manure, 

 though the effect may in certain circumstances be precisely the 

 same." 



Charlc}^ evidently thought I was wandering from the point. " You 

 think, then," said he, " manure is plant-food thtt the so'l needs f" 



"Yes," said I, "that is a very goo 1 definition — very good, 

 indeed, though not absolutely .iccurate, because manure is manure, 

 whether a particular soil needs it or not." Unobserved by us, the 

 Deacon and the Doctor had been listening to our talk. — " I would 

 like," said the Deacon, " to hear you give a better definition than 

 Charley has given." — " Manure," said I, " is anything containing 

 an element or elements of plant-foo 1, which, if the soil needed it. 

 Avould, if supplied in sufficient quantity, and in an available con- 

 dition, produce, according to soil, season, climate, and variety, a 

 maximum crop." 



