10 FARMERS' BULLETIN. 



the soil has been thorough there is little subsequent occasion for the use 

 of implements of heavy draft. A few years ago the deep subsoil plow and 

 the turning of the land for a foot or fourteen inches was considered essen- 

 tial. Now, the investigations of chemistry have demonstrated that the 

 available, i. e., the readily assimilated plant food, is that which lies close 

 to the surface, and that the deep burying of this surface soil and its 

 replacement with elements not yet sufficiently disorganized to serve as 

 plant food contained in the under soil is wasteful of both energy and 

 material. As now understood, deep plowing serves only a mechanical 

 purpose, and no more than to guarantee porosity and a free aeration of 

 the underlying beds. 



The subsoil plow has, therefore, been generally consigned to the things 

 of the past (except for uses not pertinent to this subject) and it is regret- 

 table to have to recommend its resurrection for some existing conditions 

 in this Archipelago. These conditions are mainly found upon the clay 

 cane lands, where for many years the soil has been lightly skimmed with 

 a small plow for a depth of t^o or three inches, and at this depth the soil 

 is crusted with a polished, impermeable floor, which is the reverse of what 

 is desired, and which must be broken up and pulverized if these lands are 

 to be made remunerative. That they bear unprofitable crops is no cause 

 for surprise. The real cause of surprise is that they produce even half a 

 crop of cane, and that they still do this speaks volumes for the wonderful 

 adaptability of the climate and the remarkable fertility of the land itself. 

 On such lands as these there seems no escape from the operation of the 

 subsoiler, as no other implement will quite penetrate and open up this 

 artificial hardpan. Upon virgin land any good, deep breaking plow will 

 answer, although the modern disc plows that turn a furrow of any desired 

 depth are preferred. In this plow, the rotating disc, instead of sliding 

 along the furrow, leaving a compact bottom, releases the farmer forever 

 from the perplexing question of future subsoilings. This disc plow, and 

 the double-mold-board plow for the economical building up of beds and 

 opening out drains, are the only heavy draft implements required for the 

 cultivation of cane. All subsequent tillage is prosecuted with light draft 

 disc harrows and cultivators of easy manipulation, and should properly 

 be considered under the head of "crop cultivation'' rather than that of 

 soil preparation. In stiff soils the disc plow can not be used with less 

 than three good American horses or mules, and it is doubtful if it could 

 be well operated in such lands with fewer than six carabaos. At this 

 time, when the sugar districts of the Islands have been almost depleted of 

 their live stock, it seems inopportune to recommend the doubling up of 

 draft animals by the use of heavy machinery. Still, it should be remem- 

 bered that these plows throw a furrow slice of twenty to twenty-four 

 inches, and will readily and properly prepare four to five acres in a day, 

 which is more than six carabao will imperfectly accomplish in the same 

 time with the small plow now in general use. 



