8 GENERAL ADVICE 



and is not visible as free water. As soon as the 

 moisture begins to depart from the superincumbent 

 atmosphere, evaporation begins from the surface 

 of the land. Any body which is interposed be- 

 tween the land and the air checks this evaporation : 

 this is why there is moisture underneath a board. 

 It is impracticable, however, to floor over the gar- 

 den with boards, but any covering will have the 

 same effect, but in different degree. A covering 

 of sawdust or leaves or dry ashes_will prevent the 

 loss of moisture. So will a covering of dry earth. 

 Now, inasmuch as the land is already covered with 

 earth, it only remains to loosen up a layer or 

 stratum on top in order to secure our mulch. 



All this is only a roundabout way of saying that 

 frequent shallow surface tillage conserves moisture. 

 The comparatively dry and loose mulch breaks up 

 the capillary connection between the surface soil 

 and the under soil, and while the mulch itself 

 may be useless as a foraging ground for roots, 

 it more than pays its keep by its preventing of 

 the loss of moisture ; and its own soluble plant- 

 foods are washed down into the lower soil by the 

 rains. As often as the surface becomes compact, 

 the mulch should be renewed or repaired by the 

 use of the rake or cultivator or harrow. People 

 are deceived by supposing that so long as the 

 surface remains moist, the land is in the best 

 possible condition; but a moist surface only 

 means that water is rapidly passing off into "the 



