u8 



Commercial Gardening 



dryness by saturating both soil and atmosphere with moisture with the 

 hose or water pot. The only market gardeners who do the same thing 

 in the open air in a systematic manner are the intensive cultivators or 

 maratchers in France and Holland. British fruit-growers and market 

 gardeners, owing to the large areas they crop, find it physically impos- 

 sible to apply sufficient moisture to their crops; hence they suffer great 

 losses in dry seasons. 



The diagram (fig. 89) will give an idea as to how water either rests 

 on the surface of the soil if hard and caked, or how it sinks down to 

 a depth of 1, 2, 3, or more feet if the soil has been broken up to such a 

 depth. It is obvious from the diagram, in which the soil has become 

 hard and baked, or is of a clayey nature and uncultivated, that most of 

 the rain that falls remains on the surface, and will be soon evaporated. 

 In the diagram, where a similar soil has been cultivated and turned up 

 more or less deeply, more water will sink into the soil, and it may be 

 taken that the powers of absorption will be as stated on p. 120, according 



A B C 



Fig. 89. Diagram showing Soil dug 1 ft. (A), -2 ft. (B), and 3 ft. (c) deep at the shaded portions. 

 The unshaded portions show the hard, impervious, and unbroken subsoil 



to the nature of the soil. The deeper, therefore, a soil is cultivated, the 

 more moisture it will hold for the benefit of the crops. 



LOSS Of Water through the Leaves. In addition to the water lost 

 by natural evaporation and by shallow cultivation, a vast loss is sustained 

 owing to the moisture that is given off from the leaves of the crops. 

 Stephen Hales (b. 1677, d. 1761) was the first to discover that leaves gave 

 off moisture, and an account will be found in his Vegetable Staticks, or 

 Experiments on the Sap of Vegetables, published in 1727. The quantity 

 of water taken out of the soil by various crops is stated by H. W. Wiley, 

 in his Agricultural Analysis, to be as follows per acre: 



The accuracy of these figures may be doubted. If an acre of Sun- 



