24 CONSERVATIVE LUMBERING AT SEWANEE, TEJSTN. 



obstruction to the wind which sweeps the Chestnut Ridges and sucks 

 out the leaves from the deeper hollows, depositing them on Hickory 

 Slope and Oak Flat. Fires therefore seldom burn on the Chestnut 

 Ridges and in the hollows, but occur very often and with disastrous 

 effect on the deeply littered Hickory Slope and Oak Flat. 



Although their condition is favorable for fires, the coves are less 

 exposed to them than is the plateau, because of the absence of farms 

 and. except in the case of one cove, of the railroad. Trees with 

 charred butts occur here and there in the coves; but they do not, as on 

 the plateau, form the bulk of the forest. There is undergrowth in the 

 coves, and plenty of humus — a favorable condition which, but for the 

 fires, would also exist upon the plateau. 



CAUSED OF FIRE. 



Most tires at Sewanee occur in the early spring and late fall. They 

 are usually set by railroad locomotives, farmers, nut-gatherers, or 

 visitors to the woods. The raih*oad is responsible for some fires, but 

 not for as many as are laid at its door. It is. for example, often 

 charged with setting fires which had their origin on the windward side 

 of the track, far beyond the reach of sparks. Farmers burn off the 

 leaves and underbrush to improve the pasturage; nut-gatherers set 

 the leaves afire in the fall to expose the nuts and crack the husks: and 

 visitors, thoughtless or careless of consequences, drop lighted matches 

 or burning tobacco in the forest. 



EFFECTS (IF FIRE OX THE TREES. 



The susceptibility of the trees to fire depends largely upon the 

 protection their bark affords them. The bark of Tulip-tree. White 

 Ash. Cucumber-tree, and White Basswood is thick, but it burns 

 through very rapidly; while that of hickory, although much thinner, 

 is hard to ignite, and affords a better protection. The oaks, especially 

 Scarlet Oak. are protected by an excellent fire-resisting bark, thick 

 and corky. Young trees, because their bark is thinner and their 

 crowns nearer the ground, are more easily injured than old trees: and 

 seedlings a year old will die altogether if their leaves are burned away, 

 although in their second year and afterwards their roots will sprout. 

 The season in which the fire occurs, and the health of the tree, are 

 factors which have much to do with the damage done the forest by 

 burning. A tree burned in the spring before the sap has begun to 

 rise is more likely to recover than one burned in the season of vege- 

 tation. Exhaustion due to attacks of insects and fungi, to previous 

 fires, or to its efforts to secure nourishment from a poor soil, renders 

 the trees less able to withstand a severe burning. Enfeebled by so 

 severe a drain on its strength, sprouting is unlikely after the death of 



