50 Pretz: FLoRA OF LEHIGH COUNTY, PENNSYLVANIA 
A large proportion of the area of the county is given over to 
agriculture but there is a large percentage of woodland in the 
vicinity of the mountains. On the South Mountains the wood is 
cut at intervals but the new growth seems to develop quickly 
enough to hold the soil cover well and to restore original conditions 
with maturing growth. The forest cover of the mostly denuded 
slopes of the Kittatinny Range is usually rather thin excepting 
on the shelflike plateau along its base, which however is also 
frequently denuded, like all our eastern wood cover. Between 
the mountains the greater proportion of woodland is along the 
slopes of the streams but there are frequent scattered areas of 
woodland, especially in the shale region, increasing northward 
toward the mountains. The forest cover of the South Mountains 
and southward is practically purely deciduous in character, but 
northward conifers begin to appear in the limestone region, in- 
creasing northward, and at places in the shale region and in the 
vicinity of the Kittatinny Range equal and perhaps outnumber 
the deciduous trees. 
As far as its flora is concerned, Lehigh County with reference 
to its zonal position must beincluded entirely within the Allegha- 
nian area of the Transition. 
In Bucks County, just south of Lehigh, and in the counties 
thence westward there occur areas where typical Carolinian species 
occur in association. These areas trend rather definitely east- 
ward and westward, roughly parallelling the mountains, and mark 
the extension northward in that direction of typical Carolinian 
assocfation. There are no such areas within Lehigh County. 
As to its position with reference to the larger rivers of the region, 
the Delaware, the Schuylkill, and the Susquehanna, which partly 
flow within Carolinian territory and aid in the extension of Caro- 
linian flora toward the mountains, Lehigh County lies between the 
Delaware and the Schuylkill. The Lehigh River is a large river 
but it is deflected eastward by the South Mountains to enter the 
Delaware without passing south of these hills. Its source is in 
Lehigh Pond in the “Poconos” of Wayne County, an area rich 
in species of normal Canadian association. Some of the species 
found in normal association in the mountains occur in the county 
along this stream. 
