22 ON THE TIMBER LANDS TRAVERSED “BY “A 
up into the air. The bark on the point of these knees is 
always very thin. In the Tennessee bottom, in addition to 
the Clark river timbers, are hackberry and box-elder. 
After crossing Tennessee river, there is considerable chest- 
nut in spots, and white oak abounds on low grounds, where it 
does not seem that there would be much protection in case of 
continuous sweeping fires. Inasmuch as this white oak and 
chestnut are found all through between the Tennessee: and 
Cumberland rivers, it seems very probable that the Cumber- 
land river was a fire barrier on the east. It should be said, 
however, that the white oak between the rivers on upland soil 
is very unhealthy, and appears to be rapidly dying out, a very 
large proportion of the trees being already dead. The 
same is true of some white oaks that appear in protected 
spots after crossing Cumberland river. If it be true that 
occasional fires have crossed over and gotten between the 
rivers, not enough to kill out the white oak, but enough to 
affect the soil in such a way that white oak will not flourish 
on it, this decay becomes one of exceeding great interest 
and importance. For, in that case, the burning off of Black 
Mountains, now taking place regularly, will soon drive from 
the forests one of the finest bodies of white oak timber: in 
the world, whether the burning be carried to sufficient ex- 
tent to injure the other timbers or not. | 
In Trigg county, between the rivers, the first iron-wood 
(hop hornbeam) and the first chestnut oak are met with. A 
change of level, of comparatively few feet, here, is sufficient 
to completely change the character of the timber. Along the 
branches, the white oak, white hickory, shag hickory, and red 
oak are good, and there is considerable elm and some lirioden- 
dron, beside the usual small growth. Red birch, sycamore, 
laurel oak, and white oak appear in plenty on Gilbert's creek, 
about one and one half miles from Cumberland river. 
On Cumberland river grow the most beautiful cotton trees 
I ever saw, reaching a diameter of four feet and a height of 
eighty. Sycamore, black ash, sweet gum, swamp red oak (the 
macrocarpa of \Nood), swamp chestnut oak, and splendid 
192 
