PLANT FORMATIONS OF THE CATSKILLS. 2/9 
has been removed long since from the Catskill forest. One iso¬ 
lated grove in Big Indian Valley was studied by the writer in Sep¬ 
tember, 1905, and it may be taken as a type of the original hem¬ 
lock formation. Tsaga, canadensis is the dominant tree, covering 
in a close growth many hundreds of acres. It is associated with 
Fagus americana (= F. ferruginea ), Acer saccharuni (= A. sac- 
charinum) , and Betula lutea, which are sparingly present in this 
type of forest. On the ground the botanist finds: Mitchella 
repens, Viola rotundifolia, Lycopodium lucidulum (ground-pine), 
Chimaphila umbellata (pipsissewa), etc., while Kalmia latifolia 
forms the shrubby undergrowth. 
White Pine Formation. At present this is found in a. few 
localities and it represents largely a second growth in the wider 
valleys, not at any considerable elevation. As a formation, it 
occurs on the sunny, lower slopes of mountains exposed to the 
noonday sun. Finns strobus is the dominant tree in pure growth, 
while beneath the pines, one finds much the same association of 
species as in the hemlock formation, herbs—such as Gaultheria 
procumbens (creeping wintergreen), Chimaphila umbellata, and 
Pyrola rotundifolia (wintergreen). 
Balsam Formation. Above 3,200-3,500 feet on the higher 
mountains, such as Cornell, Wittenberg, and Slide mountains, the 
balsam, Abies balsamea, forms an almost pure growth, associated 
with Picea mariana (= nigra), Sorbus ( Pyrus ) americana, Be¬ 
tula lutea, Prunus pennsylvanica and Acer pennsylvanicum, while 
the undergrowth of shrubs consists of Viburnum lantanoides, 
Ribes prostratum, Sambucus racemosus, Rubus odoratus (at 
lower elevations). The flowering plants of this forest forma¬ 
tion are Oxalis acetosella (wood-sorrel) ; Circaea alpina (en¬ 
chanter’s night shade) ; Viola blanda, Clintonia borealis, Cornus 
canadensis, Mitchella repens, Coptis trifolia (goldthread) ; and 
Corallorhisa multiflora; the fern, Dicksonia ( Dennstaedtia) pil- 
osiuscula, the club moss, Lycopodium lucidulum, and on the 
mossy windfalls, Cladonia rangiferina with Chiogenes hispidula 
(snowberry). On the tops of the largest boulders occurs in 
dense mats the fern, Poly podium mil gar e, and on the sides species 
of the lichen, Umbilicaria. Vaccinium pennsylvanicum (dwarf 
