









SOILS OF SOUTHERN NEW JERSEY AND THEIR USES. 35 
fare and Woodbury Creek in a low ridge reaching to 20 or 25 feet 
above tide level. Southward from Thorofare a gentle slope toward 
the interior upland begins, carrying the extreme elevation of the 
tract mapped to an altitude of 40 feet. 
SOILS. 
-.All of the lower part of the area surveyed hes within the terrace 
formation which borders the Delaware River and Bay. The basal 
materials in this vicinity consist of two rather heavy beds; one is a 
black, micaceous clay of massive structure and greasy appearance, 
which sometimes carries rather large amounts of greensand, while 
the other, higher bed, is also dark and micaceous but lacks the green- 
sand. Both layers affect the underdrainage of the soil types in the 
area. Upon the lower terrace, slight hollows and depressions remain 
more moist than the general condition because of the near presence 
of the clay. Upon the slopes the upper clay bed sometimes comes 
near enough to the surface to affect subsoil drainage and to con- 
stitute a rather sticky subsoil material underlying the surface soils 
at varying depths. 
The actual soil materials of the greater part of the area are to be 
ascribed to later stages of the deposition of river or estuarine sedi- 
ments. These sediments give rise to the sandy and sandy loam soils 
of the upland. These constitute a thin covering over all but the 
steepest slopes. The soils of the area thus owe their origin primarily 
to the deposition of the older, marine beds and to the later covering 
of these materials by a thin veneer of later river or bay deposits. 
Four soil types occupy the arable upland portion of the Thorofare 
area. These are the Sassafras sand, Sassafras sandy loam, Ports- 
mouth sandy loam, and Collington fine sandy loam. The last covers 
but a small area. In addition a considerable area of Tidal marsh, 
some swampy stream bottoms, and the rough, broken land occurring 
along the slopes from the upland to the streams were necessarily 
included. 
Sassafras sand—The surface soil of the Sassafras sand consists 
of a merely, medium sand of a brown to yellowish-brown color and is 
6 to 10 inches deep. The surface soil grades into a pale yellowish 
brown sand, usually rather loose in structure. At a depth ranging 
from 18 to 24 inches below the surface, the subsoil usually consists 
of a reddish-yellow to orange fine sand.. There is little difference in 
texture between the surface soil and subsoil. On account of the in- 
corporation of large amounts of organic manures in the surface soil 
throughout this region the surface soil frequently seems somewhat 
more coherent and loamy than the subsoil and its color is somewhat 
darker than the normal for the type. 
