PAPERS OX BIOLOGY AND AGRICULTURE 229 



Definite figures have not been obtained as to the amount 

 of woodland pasture required to support a single head of 

 stock, but most farmers agree that grass under the shade 

 of trees has much less nourishment in it for stock than 

 that grown in full sunlight. Farmers in southern Illi- 

 nois place its value for forage at about one-fifth of that 

 of good bottomland pasture. Hodgson estimates the 

 value of woodland pasture at 24 acres required for 10 

 head of stock or 2.4 acres required per head. 



DAMAGE DUE TO GRAZING 



It is very easy to see the damage done by grazing, 

 first to the trees and reproduction, and second to the soil. 

 The bark of the mature trees is damaged by rubbing, the 

 tender shoots forming the young growth are eaten off, 

 and seedlings are trampled out and killed. 



Forest soil which is normally moist and porous and 

 ideal for the growth and reproduction of trees is packed 

 hard, and growth is either retarded or completely 

 stopped. The soil, where packed by the hoofs of graz- 

 ing animals, becomes dry and dusty and the rain instead 

 of soaking into the ground runs off rapidly, leading 

 finally along paths to the formation of gullies. 



In LaSalle county Dr. George D. Fuller states that 

 not over 5 per cent of the grazed woodlands show any 

 reproduction: that in the last 25 years there has been 

 but little change in the timber: and that grazing has 

 produced woodlots which had better be called "wooded 

 pastures", so scattering are the trees. 



The need of shade for cattle is advanced as an excuse 

 for grazing the woodlands, and this is perhaps quite as 

 important as the forage which the cattle obtain. Shade 

 for stock can be provided by fencing off a portion of the 

 woods sufficient to supply shade, thus shutting out the 

 stock from the more valuable woodland. The numerous 

 photographs which have been taken by the Forest Survey 

 party show very forcibly the effects of grazing, leading 

 us to say that good timber and good grazing are impos- 

 sible on the same tract. 



(b.) Fire. Fire, the second problem of the landowner, 

 varies greatly with the region. The woodland tracts of 



