94 PRACTICAL FORESTRY IN 



practice should in many cases be abandoned. In many places, 

 especially in the yellow pine type, the best, and often the only, 

 reproduction comes up under a fallen treetop or other brush. 

 Where there is little of the old stand left, the straggling open 

 top protects the seedlings from the direct heat of the sun. 

 Yet brush not only protects the seedlings from the sun but, 

 what is more important, the leaves and broken twigs form a 

 cover which retards evaporation of moisture from the soil. 

 Over the greater part of the West the soil dries out very 

 rapidly during the dry season, and this serious retards or 

 even prevents the growth of seedlings. Even in the moister 

 regions, such as that of the Engelmann spruce type, it is very 

 necessary to conserve the moisture in the soil after logging 

 to prevent the remaining trees from being killed through lack 

 of soil moisture. A third reason why seedlings so often come 

 up only under the down treetops is that they are protected 

 from stock. Next to drought, sheep are perhaps the most 

 serious menace to reproduction, and though it would be best 

 to keep all stock off the area for several years after logging, 

 in many cases this is not practicable, and on many areas the 

 leaving of the tops on the ground is the only way to protect 

 reproduction from injury. 



"In many places after the timber has been cut off gullies 

 and washes start in the old wheel ruts, log slides, etc., and 

 these and other forms of erosion can best be prevented by 

 leaving the brush on the ground, either laid in the incipient 

 washes or scattered over the soil that is likely to wash. Brush 

 burning destroys the valuable soil cover, and on the spots 

 where the piles are burned the soil is loosened, which renders 

 it even more liable to erosion. 



"It is well known that where the forest is burned each year 

 the soil becomes poorer and poorer, because nitrogen, the 

 chief fertilizing ingredient of the soil, is given off in the 

 smoke, and only the mineral elements go back to the soil in 

 the ashes. And, what is more injurious, the humus i. e., 

 the decomposed vegetable matter in the top soil is destroyed. 

 In burning brush after logging all the fertilizing and humus- 



