84 PLANT LIFE OF ALABAMA. 
glomerates of the Coal Measures, rise to an elevation of from 1,200 to 
1,500 feet above sea level. Their summits, spreading into table-lands 
of comparatively limited extent, support a more varied and heavier 
tree growth than the table-lands of the Warrior basin, differing chiefly 
by the total absence of pines and the appearance of species common 
also to the forests of the Ohio Valley, and as yet not observed in other 
parts of the State. Oaks form the predominating forest growth of 
these highlands—white oak, mountain oak, and fine black oak. As 
observed on Monte Sano and the adjoining ridges, the typical sugar 
maple (Acer saccharum) of the North is not rarely met with on the 
summit and the highest flanks in the richest spots. Its variety (Acer 
saccharum barbatum) with smaller and sharper-lobed leaves, is more 
frequent and is widely diffused over the rocky hills which extend south- 
ward to the tertiary ridges of the Upper Division of the coast pine 
belt, associated with the cucumber tree, silver-leaf linden (Ziia hetero- 
phyla), and sweet buckeye (Aesculus vctandra). A group of fine trees 
of this last species, which is rare in Alabama, was observed on a ter- 
race of rich soil a short distance below the brow of Monte Sano. The 
trees measured from 25 to 30 inches in diameter and from 75 to 85 feet 
in height. This truly Alleghenian type, extending from the head- 
waters of the Ohio River in Pennsylvania along the mountains to the 
northwestern corner of Georgia, finds its southern limit at this point. 
The valleys skirting the detached spurs of the Cumberland Moun- 
tains are for the greater part still covered with the original forest, 
which is practically untouched by the ax. It can be said that a consid- 
erable portion of the most valuable hardwood timber found in the State 
is hidden in these secluded valleys—as, for example, in the valley of 
the Paintrock River. It is stated that in this valley, of about 35 miles 
in length, the tulip tree or yellow poplar (Liriodendron tulipifera) 
abounds in its largest dimensions, with white oak, linden, white ash, 
large sassafras, and black walnut, and with red cedar of superior qual- 
ity occupying the damp rocky recesses. 
The ridges of Subcarboniferous limestone rarely exceed an elevation 
of 1,200 feet. Their tree growth is the same as that of the forests 
which cover the gentler slopes of the limestone ledges cropping out 
beneath the sandstones which cap the summit of the higher ranges. 
On the flanks, with a deeper soil covering, the tulip tree becomes more 
frequent among the oaks, associated with the maples mentioned, and, 
more rarely, with white ash and shell-bark hickory (/Zicoria ovata). 
Black walnut (Juglans nigra) and wild cherry (Prunus serotina) are but 
rarely found even on the richest spots. Fetid buckeye (Aesculus gla- 
bra) is of rather rare occurrence on the more exposed slopes of the cal- 
careous hills, and red cedar is mingled with the hard-wood trees. Of 
the trees of smaller size, the American smoke tree (Cotinus cotinoides) 
makes its appearance on the calcareous summits and upon the shelves 
