HARROWING 157 



Large, four-section harrows covering i8 to 22 feet of surface are now 

 largely used even on smaller farms, because of the high price of farm 

 labor. One man and four horses can harrow between 30 and 40 acres 

 in a single day. Because the harrow covers territory so rapidly 

 and leaves the ground in such a good state of tilth, it should be used 

 much more generally. Harrowing produces a finer tilth of the sur- 

 face and thereby conserves the moisture already in the soil. Large 

 lumps massed together have between them much air space. Such 

 space allows the rain water to percolate to lower depths so rapidly 

 that the growing plant cannot use it. At the same time, the lower- 

 ing of the water level admits the surface air, which in turn dries out 

 the individual lumps and robs them of their moisture. Roots will 

 not develop in these open spaces, and not finding finer earth through 

 which to extend themselves, soon die from lack of moisture and 

 plant food. 



When plowing in the spring, the newly upturned furrow should 

 never be allowed to remain unharrowed over half 1 day. By harrowing 

 the ridges will he levelled, clods prevented from forming, and evapora- 

 tion reduced. To do this, the plowman will have to unhitch from 

 the plow and hitch to the harrow just before the close of each half 

 day. A small tection drag drawn by an extra horse at the time of 

 plowing also answers the purpose. A rotary disc in section just 

 wide enough to cover the newly turned furrow, and working auto- 

 matically, does the pulverizing more thoroughly than any other meth- 

 od. To the farmer in the corn districts of less than 24 inches of 

 rainfall, this matter is important. To the grower in the low, wet 

 districts, where the soil contains a large per cent of humus, the evap- 

 oration of excess moisture is desirable. 



If the ground be plowed too wet and turns over slick, then a 

 day's drying may be necessary before any harrowing is done. A 

 tooth harrow is of very little use on fall plowing, because the soil 

 has cemented together too firmly. After sod plowing has been thor- 

 oughly disced, the use of the harrow produces a finer and more uni- 

 form surface. 



When desiring to tear up pieces of sod or loosen deeply the sur- 

 face of a fall plowed field, the harrow teeth should be set straight, or 

 almost so. Where a field is harrowed twice before planting, the teeth 

 should be set at an acute angle. If the surface is of fine tilth, but a 

 little uneven, allowing the harrow to drag over completely flat will 

 do much toward producing an ideal seedbed. In all events, to se- 



