POINTS TO GAIN IN PLOWING 133 



It is undoubtedly better practice to plow earlier, when the green 

 stuff gets a good start, but is still not too high to turn under handily. 

 In this practice the weed stems are less woody, and they easily decay 

 and act as a fertilizer. Where early plowing is practiced, it is usual 

 to plow again when the second growth of weeds reaches the proper 

 state in the spring. When two plowings are given, the earth is usually 

 thrown away from the trees in the first plowing, and returned toward 

 the trees in the second plowing. But this order is sometimes reversed 

 in situations where rainfall is heavy and the soil retentive, for the dead 

 furrow between the rows often acts as a surface drain to carry off 

 surplus water, which is thus prevented from standing around the tree 

 roots. In all modes of plowing it is desirable that before the summer 

 heat comes, the surface be leveled as completely as possible. 



Too much stress can not be laid upon the importance of plowing 

 when the soil is in good condition and not otherwise. To disregard 

 this is bad enough in all soils, but it is a grievous mistake to work 

 any of the clayey soils when they are out of condition. If too wet, 

 they are puddled by the plow and dry down in hard clods, impenetrable 

 by air, and even resist water itself for a long time. When clods are 

 thus formed, it may require long effort to bring the soil back to a good 

 friable condition. The cultivation of adobe is one of the problems of 

 California agriculture. The more refractory it is, the more particular 

 care is needed to take it when it is in proper condition to work. To 

 work it when perfectly dry is simply impossible, and if it is plowed when 

 too wet and sticky, it becomes hard, lumpy, and altogether unmanage- 

 able. The condition which favors best results by tillage must be learned 

 by experience. 



Another mistake apt to be made where the orchard or vineyard 

 is but one of the branches of a mixed farm, is to put aside the plowing 

 until all the field work is done, and in some seasons the soil in the 

 orchard has become so dry that it turns up in large clods which are 

 afterwards partially reduced by the harrow, but never put in the fine 

 tilth which should be secured for the retention of moisture and other- 

 wise to encourage the growth and productiveness of the tree. 



Breaking up Hardpan. Those who advocate the use of the plow, 

 claim several advantages for it. The chief is that more thorough tilth 

 can be secured. In most, but not all soils, there is formed by cultiva- 

 tion an artificial hardpan at whatever depth the implement attains, if 

 this depth can be kept the same for many successive cultivations. This 

 hardpan, in some soils at least, becomes impervious to water and is 

 otherwise an injury to the growth of the trees. It occurs in irrigated 

 and unirrigated land alike, but probably is more quickly formed by 

 irrigation. When continuous summer cultivation is practiced, the hard- 

 pan will be found at whatever depth the teeth uniformity reach. The 

 remedy is to plow in winter just below this hardpan layer and thus 

 break it up, and then by the action of the air and rains it is reduced, 

 and cultivation may proceed as before. Where the hardpan is formed 

 by the plow, the ground should be plowed shallow one year and deeply- 

 the next, thus alternating from year to year. 



