22 



reservoir, and is able to absorb considerable amounts of precipitation 



(10). Although infiltration is aided, the water is distributed horizontally, 

 allowing it to be used by plants before it has a chance to percolate 



below the root zone. 



The surface mulch also protects the soil from drying and 

 consequent structural aberrations. Without this humus cover, clay 

 soils are subject to alternate wetting and drying, which causes cracks 

 that allow more rapid and deeper penetration of water (25). As noted 

 earlier, vertical jointing occurs in the glacial till of the Highwood 

 Bench. In such situations a surface mulch may be essential to prevent 

 rapid and excessive percolation of water below the root zone and conse- 

 quently to prevent the formation of saline seeps. 



To apply these and other ecological relationships in land 

 management and cropping practices will require integrated ecological 

 research, encompassing geology and hydrology, basic grassland ecology, 

 and plant and soil science. If the approach is limited to the traditional 

 realm of agriculture, a practical solution may be no closer than it 

 is today. 



PROSPECTS FOR RETARDATION 



Most authorities agree that saline seeps are nearly irreversible; 

 once the productivity of land is destroyed, reclamation is difficult. 

 With time, the salts can possibly be leached below the root zone provided 

 the flow of saline water is cut off. However, the principal objective 

 is prevention rather than reclamation. 



