52S 



FARMERS' REGISTER. 



[No. 9 



Principle 1. All plants exhaust the soil. 

 Plants are supported by the earth, the juices 

 with which this is impregnated forming their prin- 

 ciple aliment. Wetter serves as the vehicle for 

 conveying these juices into the organs, or present- 

 ing them to the suckers of the roots by which 

 they are absorbed; thus the progress of vegeta- 

 tion ten Is constantly to impoverish the soil, and if 

 the nutritive juices in it. be not renewed, it will at 

 length become perfectly barren. 



A soil well furnished with manure may sup- 

 port several successive crops, but each one will be 

 inferior to the preceding, till the earth is complete- 

 ly exhausted. 



Principle 2. All plants do not exhaust the 

 soil equally. 



Plants are nourished by air, water, and the 

 juices contained in the soil; but the different kinds 

 of plants do not require the same kinds of nour- 

 ishment in equal degrees. There are some that 

 require to have their roots constantly in water; 

 others are best suited with dry soils; and there are 

 those again, that prosper only in the best, and 

 most, richly manured land. 



The grains and the greater part of the grasses, 

 push up long stalks, in which the fibrous princi- 

 ple predominates; these are garnished at the base 

 by leaves, the dry texture and small surface of 

 which do not permit them to absorb much either 

 of air or water; the principal nourishment, is ab- 

 sorbed from the ground by their roots; their stalks 

 furnish little or no food for animals; so that these 

 plants exhaust the soil, without sensibly repairing 

 the loss, either by their stalks, which are cut to be 

 applied to a particular use, or by their roofs, which 

 are all that remain in the ground, and which are 

 dried and exhausted in completing the process of 

 fructification. 



Those plants, on the contrary, that are provi- 

 ded with large, fleshy, porous, green leaves, im- 

 bibe from the atmosphere carbonic acid and water, 

 and receive from the earth the other substances 

 by which they are nourished. If these are cut 

 green,the loss of juices, which the soil has sustained 

 by their growth, is less sensibly felt, as a part of it 

 is compensated for by their roots. Nearly all the 

 plants that are. cultivated for fodder are of this 

 kind. 



There are some plants which, though general- 

 ly raised for the sake of their seed, exhaust the 

 soil less that the grains; these are of the nu- 

 merous family of leguminous plants, any which 

 sustain a middle rank between the two of which I 

 have just spoken. Their perpendicular roots di- 

 vide the soil, and their large leaves, and thick, 

 loose, porous stalks readily absorb air and water. 

 These parts preserve for a long time the juices 

 with which they are impregnated, and yield them 

 to the soil, if the plant be buried in it before arri- 

 ving at maturity; when this is done, the field is 

 still capable of receiving and nourishing a good 

 crop of corn. Beans produce this effect in a re- 

 markable degree; peas to a less extent. 



Generally speaking, those plants that are cut 

 green, or whilst in flower, exhaust the soil but lit- 

 tle; till this period they have derived their support 

 almost exclusively from the air, earth, and water; 



et Succession de Culture, par Yvart. Traite de'Assole- 

 ments," par Ch. Pictet. 



their stalks and roots are charged with juices, and 

 those parts that are left in the earth after mowing, 

 will restore to it all that had been received from it 

 by the plant. 



From the time when the seed begins to be form- 

 ed, the whole system of nourishment is changed; 

 the plant continues to receive nourishment for the 

 perfecting of its seed, ftom the atmosphere and 

 the earth, and also yields to the grain all the juices 

 it had secreted in its own stalks and roots: by this 

 means the stalks and roots are dried and exhaust- 

 ed. When the fruits have arrived at maturity the 

 skeleton remains of the plant, if abandoned to the 

 earth, restore to it only a small portion of what 

 had been taken from it. 



The oleaginous seeds exhaust the soil more 

 than the farinaceous seeds; and the agriculturist 

 cannot be at too much pains to free his grounds 

 from weeds of that nature, which so readily im- 

 poverish them; especially from the wild mustard, 

 sinapis arvensis, with which cultivated fields are 

 so often covored. 



Principle 3. Plans of different kinds donot 

 exhaust a soil in the same manner. 



The roots of plants of the same genus or fami- 

 ly, grow in the soil in the same manner; they pen- 

 etrate to a similar depth, and extend to corres- 

 ponding distances; and exhaust all that portion of 

 the soil with which they come in contact. 



Those roots which lie nearest, the surface, are 

 more divided than those that penetrate deeply. 

 The spindle or tap roots, and all tbose that pene- 

 trate deeply into the earth, throw out but few rad- 

 icles near the surface, and consequently the plant is 

 supplied with nourishment from the layers of soil 

 in contact with the lower partof the root. Of the 

 truth of this I have often had proof, and I will 

 mention an example. If when a beet or turnip is 

 transplanted, the lower portion of the spindle be 

 cut off, it will not grow in length, but in order to 

 obtain its supplies of nourishment from the soil, it 

 will send out radicles from its sides, which will en- 

 able it to obtain the necessary supplies from the 

 upper layers of the soil; and the root will become 

 roundish instead of long. 



Plants exhaust only that portion of the soil 

 which comes in contact with their roots; and a 

 spindle root may be able to draw an abundance of 

 nourishment from land, the surface of which has 

 been exhausted by short or creeping roots. 



The roots of plants of the same and of analo- 

 gous species always take a like direction, if situa- 

 ted in a soil which allows them a free develope- 

 ment; and thus they pass through, and are sup- 

 ported by, the same layers of earth. For this 

 reason we seldom find trees prosper that take the 

 place of others of the same species; unless a suit- 

 able period has been allowed for producing the 

 decomposition of the roots of the first, and thus 

 supplying the earth with fresh manure. 



To prove that different kinds of plants do not 

 exhaust the soil in the same manner, it is perhaps 

 sufficient for me to state, that the nutrition of ve- 

 getables is not a process altogether mechanical: 

 that plants do not absorb indiscriminately, nor in 

 the same proportions, all the juices and salts that 

 are presented to them; but that either vitality, or 

 the comformation of their organs, exerts an influ- 

 ence over the nutritive action; that there is on the 

 part of plants some taste, some choice regarding 

 their food, as has been sufficiently proved by th* 



