280 OTTIO BIOLOGICAL SURVEY 



It bcai's a <j;t'iu'i'al I'eseiublaiice to the i)iiU' barrens coiiiiuoii everywhere 



below the l)ortU'r of the glacial moraines. Its principal component 

 species are : 



PiNUS RIGIDA Gaiiltheria i^^'ocitmhcns 



Finns virginiana Fanicum dicliotoiinim 



Quercus velutina Chimaphila maculaia 



Castanea dentata Meibomia rotundifolia 



Oxydendrum arhoreum Isotria verticillatn 



Vaccinium vacilans Soliduf/o neinorosa 



Goylosaccia baccata ;^ Houstonia loiif/ifolia 



Polycolium starniniurfi Hieracium venosum 



Kalmia latifolia Ptniicuni sphiK ro-nviion 



Epigaea repens Ciiiiilhi originoides 



Smilax rotundifolia Lespedeza liirta 



Smilax glanca Lesperesa repens 



AmaJancier canadensis Lespedeza procumbens 

 Bosa virginiana 



Togethei' with these are numerous seedlings from other associa- 

 tions. Saplings of Hicoria ovafa are nearly always present and here, 



as everywhere else, Acer ruhnini comes up abundantly but attains no 

 great size. 



The Oak Forest. The pine forest occurs throughout the region on 

 the more exposed ridges. Where the ridges become wider and the con- 

 ditions are less severe, the pines gradually give way to the hard woods 

 and a mixed oak forest is developed in which Quercus prinus is some- 

 times the dominant tree and occasionally occupies the ground almost 

 to the exclusion of other arborescent species. With it are more usually 

 present, however: 



Quercus alba Hicoria minima 



Quercus velutina Hicoria ovata 



Oxydendrum arbor earn (fig. 1<S) Nyssa sylvatica 



Castanea dentata Acer rubriim 



In the underbrush the heaths give way to the grai)evine (Vitis 

 bicolor), which is (piite as typical a representative of the association 

 as the oaks. With it are : 



Cynoxylon (Cornus) florida (an Smilax glanca 



under tree.) Bosa virginiana 



Smilax rotundifolia Viburnum acerifolium 



The most characteiistic plants of the herbage are : 

 Meibomia nudifiora Linum virginianum 



Meiboma rotundifolia Monotropa unifora 



Dasy stoma laevigata Hypopytis americana 



Titythymnlopsis (Euphorbia) corollata 



