160 ACTION OF THE SOIL ON PLANTS. 



The more tenacious and compact the soil is, the closer 

 the furrows must be, and the narrower the ridges of earth 

 turned up, in order more effectually to pulverise it, and 

 afford channels for the water to run off. When the soil 

 is light, broader ridges and more distant furrows suffice : 

 it is even sometimes necessary to beat down the earth, 

 after having ploughed or dug it, in order to render it more 

 compact, especially in nurseries of young trees, whose 

 roots, in a loose soil, are liable to be torn up by the wind. 



Deep furrows, or trenches, are very useful where the 

 ground is sloping, either to draw off or retain the water 

 as required. If the soil be too moist, the furrows should 

 be made longitudinally, that is to say, from the top to the 

 bottom of the acclivity : they will then answer the pur- 

 pose of conduits to carry off the water. If, on the con- 

 trary, the soil be dry, the furrows should be made trans- 

 versely, and the ridges of earth will act as parapet walls 

 to retain the water. 



It is very necessary also, to pay attention to the period 

 of ploughing : it can be done neither in a wet season nor 

 during a hard frost, nor in very dry weather ; but as you 

 have the whole season before you, from the reaping of 

 one harvest to the so wing for another, it is not difficult to 

 choose a period of appropriate weather, unless it be in 

 some strong clays, upon which a horse cannot be suffer- 

 ed to tread during the winter. If the ground be inten- 

 ded to lie fallow, the best use which can be made of the 

 repose allowed it, is to plough it in autumn, and again 

 in the spring ; but if it is to be sown, the sooner it is 

 ploughed after harvest the better, in order to bury the 

 straw or other remains of the preceding crop, which will en- 

 rich the soil, and also prevent the further growth of weeds. 



In hot countries the land cannot be ploughed in sum- 

 mer, on account of its dryness ; besides, it would afford 

 the means of evaporating the small remains of moisture 

 of the newly turned up earth, and that at a period, when it 

 has its most important functions to perform those of 

 softening and dissolving the hardest and most insoluble 

 particles, which cannot be done unless the temperature 

 of the water be tepid. 



880. How must the width of the furrows be regulated 1 ? 881. How 

 should they be on sloping ground'? 882. What is said of the period 

 of oloughingl 883. And if the ground is to lie fallow'? 



