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deeper a plough could be run, the better would be the results that \\ ould 

 follow. The injurious results of such practice can not be estimated 

 without careful study of the root-systems of orange trees on various 

 stocks and soils. A number of bearing citrus groves were so much 

 injured by the reckless use of s-ubsoil ploughs that the leaves of the- 

 trees actually wilted down immediately after the operation. In these 

 cases, the sharp-cuUing plough was run close to and on all sides o^ the 

 trees. When trees over ten years of age, which have been subjected 

 to uniform shallow ploughing and irrigation, are submitted to such 

 treatment, they probably lose at one blow not less than seventy-five 

 per cent, of their active roots. The shock is such that it would take- 

 several J ears of careful treatment to restore the trees. 



Practical Notes on Deep Cultivation and Irrigation. — It is almost 

 always more economical to use a sub soiler or plough where " irrigation 

 hard pan" has been formed than it is to use the large amount of water 

 necessary to soften it, but according to the best practice the deepening 

 of cultivation should be gradual, and the implement should never run 

 deeper than fifteen inches. One must rem^ mber that the re;illy serious 

 loss in sudden deep cultivation comes from the destruction of thousands' 

 of fibrous roots that grow from the hundreds of laterals branching' 

 from the large main roots. 



If a plough is run to a depth of one foot, in three furrows, between the 

 rows, and water percolates slowly for a long time through these fur- 

 rows, no need can arise for a subsoiler. "Irrigation hardpan" within, 

 reach of the plough simply shows, as hasbpen said, that too shallow and 

 too uniform cultivation has been practiced. In that case the entire- 

 surface should be thoroughly broken up, and irrigation in deep fur- 

 rows after this will restore the proper conditions. 



Experience also shows that when the water is slowly run in deep- 

 furrows for a long time and the greater part of the surface is kept dry 

 and is deeply cultivated, better results are obtained than when the 

 basin or block method, or even the shallow-furrow plan is used, even 

 though they are followed by deep cultivation. When the water is ap- 

 plied below the first foot of soil, and the soil above is kept compara- 

 tively dry, there is nothing to attract the roots to the surface ; and when 

 the water is thus applied, a team can be driven along the dry strips of 

 of land between the furrows, and with a harrow or other appliance the 

 dry soil can be dragged into the wet furrows, to lessen the evaporation, 

 immediately after the irrigation water is turned off. By any other 

 system, it is absolutely necessary to wait at least twelve hours, and 

 sometimes much longer, before a team can be driven over the ground. 

 Then, too, when a soil irrigated by these more wasteful methods has 

 been cultivated, it is still moist near the top, and is soon filled with a 

 mass of new roots so close to the surface that they must be destroyed. 



Waste from Evaporation of Water. Water applied to the soil sinks 

 and spreads. Some of it is being taken up by the still dry soil under- 

 neath and at the sides long after the last drop is visible. fSome of it 

 too, is being drawn back to the surface, and thence evaporated into 

 the warm air. Irrigation after sundown has some distinct advantages 

 if the water can be handled. Sub-irrigation upon soils adapted to its 

 use is the ideal system of applying water, and greatly lessens Avaste. 

 Orange roots will not enter a pipe-line unless it is full of water all the 



