160 DRY-FARMING 
over thoroughly several times if necessary, with an 
iron tooth harrow, the teeth of which are set to slant 
backward in order not to tear up the plants. The 
loose earth mulch thus formed is very effective in 
conserving moisture; and the few plants torn up are 
more than paid for by the increased water supply for 
the remaining plants. The wise dry-farmer culti- 
vates his land, whether fallow or cropped, as early 
as possible in the spring. 
Following the first spring plowing, disking, or culti- 
vation, must come more cultivation. Soon after the 
spring plowing, the land should be disked and then 
harrowed. Every device should be used to secure 
the formation of a layer of loose drying soil over the 
land surface. The season’s crop will depend largely 
upon the effectiveness of this spring treatment.. — 
As the season advances, three causes combine to 
permit the evaporation of soil-moisture. 
First, there is a natural tendency, under the some- 
what moist conditions of spring, for the soil to settle 
compactly and thus to restore the numerous capillary 
connections with the lower soil layers through which 
water escapes. Careful watch should therefore be 
kept upon the soil surface, and whenever the mulch 
is not loose, the disk or harrow should be run over 
the land. 
Secondly, every rain of spring or summer tends to 
“establish connections with the store of moisture in 
the soil. In fact, late spring and summer rains are 
