183G.J 



FARMERS' REGISTER 



529 



experiments of Messrs. Davy ami de Saussure. 

 It is with plants as it is with animals — there are. 

 some elements common to all, and some peculiar 

 to each kind: this is placed beyond doubt, by the 

 preference given by some plants to certain salts, 

 over others. 



Principle 4. All plants do not restore to the 

 soil either the same quantity, or the some, quality of 

 manure. 



The plants that grow upon a soil, exhaust more 

 or less of its nutritive juices, but all return to it 

 some remains, to repair a part of its loss. The 

 grains and the oleaginous seeds may be placed at 

 the head of those which exhaust a soil the most, 

 and repair the least, the injury done it. In those 

 countries where plants are plucked up, they return 

 nothing to the soil that has nourished them. 

 There are some plants, to be sure, besides those 

 mentioned above, that by forming their seed, con- 

 sume a great part of the manure contained in the 

 in the soil; but the roots of many of these soften 

 and divide the soil to a considerable depth; and 

 the leaves which fall from the stalk during the 

 progress of vegetation, restore to the earth more 

 than is returned by those before mentioned. There 

 are others still, the roots and stalks of which, re- 

 maining strong and succulent after the production 

 of their fruits, restore to the soil a portion of the jui- 

 ces they had received from it; of this kind are the 

 leguminous plants. 



Many plants that are not allowed to produce 

 seed, exhaust the soil but very little; these are 

 very valuable in forming a system of successive 

 crops, as by introducing them into the rotation, 

 ground may be made to yield for many years 

 without the application of fresh manure; the va- 

 rieties of trefoil, especially clover and sainfoin, are 

 of this sort. 



Principle 5. All plants do not foul the soil 

 equally. 



It is said that a plant fouls the soil, when it. fa- 

 cilitates or permits the growth of weeds, which 

 exhaust the earth, weary the plant, appropriate to 

 themselves a part of its nourishment, and hasten 

 its decay. All plants not provided with an exten- 

 sive system of large and vigorous leaves, calculated 

 to cover the ground, foul the soil. 



The grains, from their slender stalks rising into 

 the air, and their long, narrow leaves, easily ad- 

 mit into their intervals those weeds that grow 

 upon the surface, which being defended from 

 heat and wind,grow by favor of the grain they in- 

 jure. 



Herbaceous plants, on the contrary, which co- 

 ver the surface of the soil with their leaves, and 

 raise their stalks to only a moderate height, stifle 

 all that endeavors to grow at their roots, and the 

 earth remains clean. It must be observed, how- 

 ever, that this last is not the case unless the soil 

 be adapted to the plants, and contain a sufficient 

 quantity of manure to support them in a state of 

 healthy and vigorous vegetation; it is for want of 

 these favorable circumstances that we often see 

 these the same plants languishing, and allowing 

 the growth of less delicate herbs, which cause 

 them to perish before their time. Vegetables sown 

 and cultivated in drills, as are the various roots and 

 the greater part of the leguminous plants, allow 

 room for a large number of weeds; but the soil can 



Vol. Ill— 67 



be easily kept free, by frequent use of the hoe or 

 weedingfbrk; and by this means may be preserved 

 rich enough for raising a second crop, especially if 

 the first be not allowed to go to seed. 



The seeds that are commited to the ground often 

 contain those of weeds amongst them, and too 

 much care cannot be taken to avoid this; it is more 

 frequently the case, however, that these are 

 brought by the winds, deposited by water, or 

 sown with the manure of the farm-yard. 



The carelessness of those agriculturists who al- 

 low thistles and other hurtful plants to remain in 

 their fields, cannot, be too much censured; each 

 year, these plants produce new seeds, thus ex- 

 hausting the land and increasing their own num- 

 bers, till it becomes almost impossible to free the 

 soil from them. This negligence is carried by 

 some to such an extent, that they will reap the 

 grain all round the thistles, and leave them stand- 

 ing at liberty to complete their growth and fruc- 

 tification. How much better it would be to cut 

 those hurtful plants before they flower, and to add 

 them to the manure of the farm. 



From the principles which I have just estab- 

 lished, we may draw the following conclusions. 



1st. That however well prepared a soil may be, 

 it cannot nourish a long succession of crops with- 

 out becoming exhausted. 



2d. Each harvest impoverishes the soil to a cer- 

 tain extent, depending upon the degree of nourish- 

 ment which it restores to the earth. 



3d. The cultivation of spindle roots ought to suc- 

 ceed that, of running and superficial roots. 



4th. It is necessary to avoid returning too soon 

 to the cultivation of the same or of analogous 

 kinds of vegetables, in the same soil.* 



5th. It is very unwise to allow two kinds of 

 plants, which admit of the ready growth of weeds 

 among them, to be raised in succession. 



6th. Those plants that derive their principal sup- 

 port from the soil, should not be sown, excepting 

 when the soil is sufficiently provided with ma- 

 nure. 



7th. When the soil exhibits symptoms of ex- 

 haustion from successive harvests, the cultivation 

 of those plants that restore most to the soil, must 

 be resorted to. 



These principles are confirmed by experience; 

 they form the basis of a system of agriculture rich 

 in its products, but more rich in its economy, by 

 the diminution of the usual quantity of labor and 

 manure. All cultivators ought to be governed by 

 them, but their application must be modified by 

 the nature of soils, and climates, and the particular 

 wants of each locality. 



To prescribe a series of successive and various 

 harvests, without paying any regard to the difier- 



* In additions to the reason I have given why plants 

 of the same or analogous kinds should not be cultiva- 

 ted in succession upon the same soil, there is another 

 which I will here assign. M. Olivier, member of the 

 French Institute, has described with much care all the 

 insects which devour the neck of the roots of grain; 

 these multiply infinitely if the same or analogous kinds 

 of plants be presented to the soil for several successive 

 years; but perish for want of food whenever plants not 

 suited to be food for their larva 5 , are made to succeed 

 the grains. These insects belong to the family of Ti- 

 pulse,or to that of flies. (Sixteenth Vol. of the Me- 

 moirs of the Royal and Central Agrieullural Society of 

 Paris.) 



