J 



656 Harshberger : Plant formations of Nockamixon Rocks 



Talus vegetation 



Facies species : Fagus americana {F. grandifolid), Acer Sac- 

 chartiin^ Betula lenta. 



Dominant species : Tilia americana^ Ulnms americana, Qiierciis 

 Prinus, Ulmns racemosa^ Fraxinus americana, F. pnbescens (/^ 

 pen nsykf ante a\ Acer rubriim, Carpinus caroliniana, Ostrya vir- 

 ginianay Juglans cincrea, J, nigra. 



Uncommon species : Acer nigrum {A, Saccharnm, var. 7iigruni), 

 Morns rnbra, Celtis occidentalism Robinia Pseudo-acacia. 



Gregarious species : Tsuga canadensis, Jnnipcriis virgifiiana. 



Rare species : Betula nigra, Liriodendron Tulipifera, 



Very rare trees : Castanea dentata, Platantis occidentalis. 

 The absence of the white oak, Quercus alba, and the almost entire 

 absence of the chestnut, Castanea dentata, and the tulip tree, 

 Liriodendron Tidipifera, are noteworthy. The facies, consisting of 

 beech, sugar maple, and cherry birch, suggests a similar one in 

 the Catskill and Adirondack mountains, which I have denominated 

 elsewhere * the beech-maple-birch facies. 



Secondary tree species (underwood): The secondary species 

 of the talus are those which can grow under the leafy canopy of 

 the dominant trees of the forest Such are Acer pennsylvaniciim, 

 Prunus americana^ P. virginiana, P. serotina, Hamanielis virginiana , 

 and RJwdodendron maximum, which occurs in association thickets. 



Shrubby undergrowth (third layer = Niederwuchs) : The 

 species are arranged in the order of their prevalence, as follows : 

 Taxits canadensis, Hydrangea arborescenSy Acer spicatunt, Staphylea 

 trifolia, Physocarpus opidifolius, Dieridlla trijida {D. Lonicerd), 

 Vibur7ium acerifolium, Cornns circinata, C. paniculata, Riibus 

 odoratus, R, occidentalism and Sambnciis racemosa. The yew forms 

 extensive matted growths on the rough talus slopes and is one of 

 the most abundant of the plants which are found as an under- 

 growth in the forest It occurs also on the upper cliff slopes near 

 the crest. Here and there along the road at the edge of the 

 forest are colonies of the staghorn sumach, RJius typhina. It is 

 hardly to be included as a component of the natural vegetation of 



* Harshberger, John W. The plant formations of the Adirondack Mountains, 

 Torreya 5 : 187-194* 1905, The plant formations of the Catslvills, The Plant World 



8: 276-281. 1905. 



