Vegetation of Stone Mountain 91 
SOME ASPECTS OF STONE MOUNTAIN AND ITS VEGETATION. 
ELMER GRANT CAMPBELL. 
Stone Mountain is a huge dome-shaped rock, situated sixteen miles 
east of Atlanta, Georgia. It measures seven miles in circumference at 
its base and rises 686 feet above the adjacent land surface. This 
mighty stone includes 663 acres of exposed granite area.’ 
The purpose of this paper is to give a panoramic view of Stone 
Mountain and its remarkable vegetation.* This view is prefaced by 
geological and botanical notes from some of the literature relative to 
the subject. 
Geology. 
Dr. Thomas L. Watson has set forth an invaluable collection of 
data concerning the geology of this most wonderful stone,’ a small por- 
tion of which follows: 
“Stone Mountain forms one of the few conspicuous, unreduced, 
residual masses found rising above the general surface-level of the 
Georgia Piedmont Tertiary peneplain. That this and the adjacent 
masses of hard contorted granite-gneiss, in the Lithonia area to the 
south, were not reduced to the same approximate level of the surround- 
ing plain, can be readily accounted for, by differential rock-hardness, 
and remoteness from the major streams in the region. ‘ 
“The chemical composition of this granite mass is chow in the 
two following analyses made by Mr. R. L. Packard in the laboratory 
of the Survey from specimens collected by Professor Yeates from the 
Hayne quarry: 
I II 
SUNT CAR eshte esate aslo Senos aere & 72.56 TUL 
DAMIAN TINA Bare ess aie shat hote een a ete 14.81 16.05 
NiO ne OXTCeb oy hae teen Akcestae a tok are 0.94 0.86 
ATi ty, iro te ks Pang eee tine erie eae Ib gale) 1.07 
IAT IEe CRT, Aes ae ee ae ee SPR a 0.20 Ope, 
ISYOXG FE): aa kG cee earn ae ce a ean 4.94 4.66 
Ropach theses sas aees cis ctesge ereaans att 5.30 4.92 
enitrOmMm tyne eo tiac lees ae eon seer ores 0.70 1.00 
MNO Gea trons veh > oe epsrtas ssc aceueuometeee ewetey.2 100.64 . 100.39 
I. Analysis of the perfectly fresh rock. 
II. Analysis of a spawl, which was exposed for three or four years 
on the dump-pile at the quarry. 
“Physical tests made on the Stode Mountain granite yielded the 
following figures: 
SIDZOING’ CATEN AIA 4 GoStats O ppc cre One dene ms Oleke Bsc eee ae eect 2.686 
Weight of one cubic foot of stone expressed in pounds......... 167.90 
1 Bulletin 9A Geological Survey of Georgia. 
* The study was made in September, 1916. 
