70 College of Forestry 
plateau in New York and the more boreal ones into the 
higher Adirondacks. 
On the Atlantic slope with its maritime conditions the 
various species groups extend correspondingly farther north- 
ward, the oak, hickory, chestnut and associates over New 
England, and the maple, beech, birch, hemlock and pine to 
make the dominant forest elements of the maritime provinces 
of Canada. Of course, also, the coastal plain species (sand 
strand vegetation of Harshberger, sand barren species of New 
Jersey, Long Island coast, etc.), extend correspondingly far 
to the north. 
With regard, finally, to the alpine flora of the highest 
peaks of the Adirondacks, it also is held to be a relict flora of 
this post-glacial migration," but see further, page 79. 
Suggested Zones and Their Indicator Species. 
A. Zone of Willow Oak, Sweet Gun, Persimmon, Ete. 
Indicator Species. 
Short-leaf pine (Pinus echinata Mill.). 
Willow oak —=(Quercus phellos L.). 
Oak —= (Quercus pogodaefolia (Ell.) Ashe). 
Black-jack oak =(Quereus marilandica Muench.) . 
Laurel magnolia Magnolia virginiana L.). 
Sweet gum Liquidambar styraciflua L.). 
II II 
ane a 
IH ML A 
Hop tree (Ptelea trifoliata L.). 
Mistletoe — (Phoradendron flavescens(Pursh.) Nut- 
tall). 
Virginia spiderwort = Tradescantia virginiana L.). 
Day flower =(Commelina virginica L.). 
Tn addition to these and others perhaps equally important, 
the species of Zone B and many of Zone C. 
DisTRIBUTION AND Exrrent: Staten Island, southern 
Long Island, especially coastward, and a narrow belt border- 
ing the Sound from Manhattan and the Bronx to and con- 
tinuing along the Connecticut coast. Growing period (esti- 
mated from last frost of spring to first of fall) 190 to 200 
days. 
1 Adams, C. C. Post Glacial Origin and Migration of the Life of 
the Northeastern United States. Jour. Geo., 1:1902, Nos. 8 and 9. See 
especially p. 309. Also Harshberger, J. W.: Phytogeographic Survey of 
North America. In Die Vegetation Der Erde XII1:1911. In this con- 
nection, p. 189. 
