THE IRBIGATION AGE. 



79 



an instinct that does not faff far short of the marvelous. 

 For instance, in the arid regions the plant sends its 

 roots down deep and out in every direction after the 

 moisture which it apparently knows it can not get at 

 the surface or near it, whereas, in the humid regions, 

 the roots spread out more, because they apparently 

 know that the moisture is near the surface and they 

 do not have to toil so hard to make their way down 

 deep. Anyone practicing surface irrigation will know 

 that the roots of plants which have a habit of penetrat- 

 ing deep into the soil, grow along the surface, because 

 the moisture is there. Plants always adopt the easiest 

 method of obtaining food. 



Now why do plants travel after moisture and not 

 after dry soil? It is not water plants need, nor is it 

 moisture, but it is food. They know that there is food 

 material in the dry soils, but it is not in a fit condition 

 to be absorbed, whereas, moisture prepares the food for 

 them, hence they refrain from pursuing the raw ma- 

 terial and expend their energies in seeking the manu- 

 factured product. Let a garden patch which has been 

 kept moist, and in which the roots congregate, be allowed 

 to dry, and another patch that has been dry and away 

 from which the roots turn, be moistened, and the plants 

 will grow away from their former hunting ground and 

 in the direction of the new one. This is common ob- 

 servation. A beet root has been known to travel sixteen 

 feet in the direction of a well where it knew it could 

 get a drink, although plants, as a rule, are not drinkers 

 but feeders of the most pronounced Epicurean type. 



In the arid and semi-arid regions it is better to 

 provide for a deep burrowing of the roots, because when 

 they frequent the surface, they are liable to suffer from 

 drought, or surface dryness. In this the reader will 

 find an argument in favor of sub-irrigation. 



Upon this instinct of roots to seek their proper food 

 in moist soil, depends the measurement of soil tillage, 

 whether deep or shallow, and by "shallow" is not meant 

 a mere surface scratching, but a good wholesome up- 

 heaval of the soil from a depth of eight to twelve inches, 

 thence on up to eighteen if the subsoil be in question. 

 Where the subsoil is not hard packed, then as deep as 

 the subsoil; if packed it should be broken up. But 

 where the subsoil is open and porous there is less need 

 of deep plowing; on the contrary, it may be necesary to 

 pack the bottom of the furrow, which is accomplished 

 by a plow attachment known as a "packer," so arranged 

 as to follow the plow and press down the earth at the 

 bottom of the furrow; a useful contrivance where irri- 

 gation is practiced, inasmuch as it tends to prevent the 

 leaching of the irrigation water down into the porous 

 subsoil, where the water is run into the furrows. 



It can not be too strongly impressed upon the 

 reader that the soil must be so cultivated that it will 

 retain moisture without permitting it to leach beyond 

 the reach of the roots, and at the same time so broken 

 up and pulverized that the roots may easily penetrate. 

 Let this be the axiom constantly in mind : Give the 

 plant roots room to spread. Upon this depends the 

 perfection of the plant. "Stunts" are always caused by 

 too little root room, the plant languishing because 

 they are unable to reach moisture by reason of obstacles 

 in the soil. If there is any moisture in the soil the 

 plant will get it if it be given an opportunity. 



Let us assume that we have a parcel of land in 

 which it is purposed to grow plants without the appli- 

 cation of manure. It does not matter whether it be 

 virgin soil or one that has already grown a crop of any 



kind; the first thing to be done to this land is to im- 

 prove the soil, that is, prepare it for vegetation. This 

 may be done in seven ways : 



First By cultivation, or, more properly speaking, 

 pulverization of the soil, by plowing and other mechan- 

 ical means of reducing its consistency. 



Second By mechanical consolidation. 



Third By exposure to the atmosphere; that is, 

 "fallowing." 



Fourth By alteration of its constituent parts. 



Fifth By changing its condition in respect to 

 water. 



Sixth By changing its position in respect to at- 

 mospheric influences. 



Seventh By a change in the kinds of plants cul- 

 tivated, or "rotation of crops." 



PLOWING AND PULVERIZING. 



All these different methods of preparing the soil 

 means practically the same thing the breaking up of 

 the soil, which must be done constantly if a good crop 

 in quantity and quality be desirable. 



By reason of their chemical elements the tendency 

 of all soils is to concrete; that is, to run together into 

 a sort of ntore or less hard cement, a tendency enhanced 

 by the growing of crops and the application of water, 

 or either. Thus, sand without consistency and quick- 

 lime without coherence, when mixed together with 

 water, produce a hard cement or plaster, which may be 

 crushed and pulverized before it can become again man- 

 ageable. In soil the chemical agencies of nature are 

 constantly at work to produce the same result; hence 

 cultivation to break up a tendency which is adverse 

 to the growth of plants and free root penetration. 



The very first object of cultivation is to give scope 

 to the roots of plants to spread in every direction, for 

 without abundance of roots no plant can become vigor- 

 ous, whatever may be the richness of the soil in which 

 it is placed. The quantity of food taken from the soil 

 does not depend alone upon the quantity in the soil, 

 but on the number of absorbing root fibres. The more 

 the soil is pulverized the more the fibres are increased, 

 the more food is obtained, and the more vigorous the 

 plant becomes. Any house plant growing in an earthen- 

 ware pot will demonstrate this. The roots grow down 

 and then, finding an obstruction, begin growing round 

 and round in search of food, until the entire pot is 

 filled with root fibres, even forcing out the soil to find 

 room, and when they have grown to the limit of their 

 confined space, the plant stops growing and becomes 

 sickly. 



This cultivation or stirring up of the soil for root 

 expansion is not only essentially precious to planting, 

 or sowing, but highly beneficial afterward, during the 

 progress of vegetation ; and when practiced in the spaces 

 between the plants it also operates as a method of 

 root-pruning, by which the extended fibres are cut off, 

 or shortened, thereby causing them to throw out numer- 

 ous other fibres whereby the mouths or pores of the 

 plants are greatly increased, and their food capacity 

 enhanced. It is very much like fattening animals for 

 market by encouraging their consumption of fattening 

 food. 



Cultivation renders capillary attraction more uni- 

 form, this peculiarity of the soil being greater when the 

 particles of earth are finely divided. Thus, gravels and 

 sands scarcely retain water at all, while clays, not opened 

 by pulverization or other means of breaking them up 4 

 either do not readily absorb water, or when exposed 



