8 BULLETIN 1005, U. S, DEPARTMENT OF AGRICULTURE. 
Portsmouth series. — The types included in the Portsmouth series 
are characterized by dark-brown to black surface soils and by gray to 
slightly mottled gray and yellow subsoils. In some places the deeper 
subsoil is almost white. The surface soils are normally high in 
organic matter. The Portsmouth soils represent swampy accumu- 
lations. The series is poorly drained in its natural condition and 
occupies depressions, broad level areas, and stream margins. It is 
the common soil condition of the marginal portions of the Dismal 
Swamp. Cultivation to quite a variety of crops is possible where 
drainage has been adequately established. 
Swamp. — The Swamp areas of the region consist of the Dismal 
Swamp and numerous small tracts of undrained land. The soil 
material consists chiefly of an accumulation of organic matter with 
varying proportions of mineral matter, the latter having been washed 
or blown into the swampy areas. The Swamp is largely forested, but 
considerable tracts of once swampy land have been cleared and 
drained, both mthin the limits of the Dismal Swamp and around its 
margins. In almost all cases such tracts are found to possess soils of 
the Portsmouth series, although small areas of peat are also 
encountered. 
Dunesand. — Along the coast line, particularly in the vicinity of 
Cape Henry, there are great accumulations of medium to fine tex- 
tured wind-blown sand. Part of this material has been heaped up 
into dunes 15 to 70 feet in elevation, while other large tracts consist 
of low ridges and intervening hollows of plains of wind-swept sand. 
Many of these areas are covered with a thick vegetation of live oak 
and pitch pine; others are bare of vegetation. 
Such a wide diversity of drainage and soil conditions naturally 
gives rise to a considerable difference in the degree to which different 
localities are utilized for agriculture and to a discriminating occupa- 
tion of different soil types for use in the intensive business of truck 
crop production. 
DETAILED SOIL AND CROP MAPS. 
Dm-ing the- fall of 1915 and the summer of 1916 surveys were made 
in the vicinity of Churchland and Diamond Springs, Va., to show the 
relationships that exist between the soils of the Norfolk trucking dis- 
trict and the distribution of the more important crops grown. The 
Churchland area is fairly representative of the trucking area along 
the Western Branch of the Elizabeth River, extending thence to the 
Nansemond River. The Diamond Springs area represents the con- 
ditions that exist in the northern part of Princess Anne County, 
where truck crops are also extensively grown. 
