The Soil Reactions of certain Rock Ferns—II 
EDGAR T. WHERRY 
Asplenium ebenoides appears to have been found most 
frequently on limestone, although its type locality was 
on gneiss or schist, and at the famous occurrence at 
Havana, Alabama, the rock is described as a conglomer- 
ate. At several stations located by Messrs. Pretz and 
Young near Allentown, Pennsylvania, and Natural - 
Bridge, Virginia, respectively, the rocks are limestone, 
and the soil reactions alkaline or, where the fern grows 
in moss coating the rocks, slightly acid. Near Harper’s 
Ferry, West Virginia, a plant kindly shown to the writer 
by Dr. T. C. Stotler grows on shale, and the soil is minim- 
acid. The soils in the pockets in schist rock, where this 
species has been found along the Potomac northwest of 
Washington, are likewise moderately acid. The soil on 
herbarium specimens collected by Mr. Maxon at Havana 
was found to have a high minimacid reaction. This 
fern is therefore inferred to be a calcareous soil plant, 
somewhat tolerant of acid conditions. 
Asplenium platyneuron (ebeneum) grows with appar- 
ently equal frequence in both moderately acid and alka- 
line soils, the statement sometimes made that it prefers 
limestone coming apparently from the lack of apprecia- 
tion of its abundance and luxuriance in many regions 
where there occur no limestone or other calcareous rocks 
whatever. It is interesting to note, however, that this 
fern tends to avoid soils of greater acidity than subacid, 
and when growing in regions of dominant mediacid soils, 
as in the Pine-Barrens of New Jersey, it is most often 
found on steep banks where soils of subacid reaction are 
developed. In southern Delaware it occurs in isolated 
patches in pine woods, and tests have shown the soils of 
these areas to be distinctly less acid than are those of the 
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