52 BULLETIN" 140, U. S. DEPARTMENT OF AGRICULTURE. 
If most of the sand is fine, rather than medium or coarse, the type 
is a fine sandy loam. When still more of the clay and silt are 
included, so that the proportions of sand and fine material are about 
equal, thus obscuring largely the grittiness of the sand, the soil is 
a loam. 
When the clay and silt particles predominate only the fine grades 
of sand are usually present. If the silt grade is most abundant the 
soil is a silt loam. If clay is greatest in amount, the soil is a clay 
loam. And if the exceedingly fine clay particles constitute more than 
30 per cent of the soil mass, the type is a clay, the other TO per cent 
being primarily of silt and very fine sand. A soil containing as much 
as 50 per cent clay is very " heavy," while those containing 60 to 70 
per cent, as along Lake Superior and Lake Champlain, are exceed- 
ingly stiff and hard to work. 
The classification in the above table refers to surface soils. Where 
surface soils differ materially in color, as red and yellow, even though 
derived from similar geological materials, as the Wethersfield and 
the Micldlefielcl soils, they are placed in different series. If iayo 
identical surface soils are underlain by subsoils, one of a sandy 
nature and the other clayey, they also are, or should be, placed in 
different series, as the light and heavy subsoils of the Gloucester 
series. If two soils and subsoils are identical in texture and color, 
but differ in the character of the geological material from which 
they are derived, as limestone and granite, they are placed in dif- 
ferent series, to wit, the Dover and the Gloucester series. These 
distinctions all lie within a given soil province such as New England, 
or the Atlantic Coastal Plain, the Appalachian Mountains and 
valleys, etc., but on account of differences in climatic and consequent 
cropping characteristics the same series name is not used in two 
soil provinces, even though the soils are similar in color and deriva- 
tion. This is illustrated in the Southern States by the Cecil and the 
Porters soils, the former occurring in the Piedmont Plateau and the 
latter in the Appalachian Mountains division. 
In the Gloucester series loams and fine sandy loams are the pre- 
dominating soil types in Massachusetts and Connecticut. Fine sand 
is next in importance, and on Cape Cod it is the most prevalent type. 
True clays and heavy clay loams do not occur. Even light clay loams 
are uncommon, heavy loams and silty loams constituting the heavy 
soils of the region. In the Wethersfield and Middlefield series the 
silt loams and the fine sandy loams are the most important types, 
though there is considerable loam and a little sandy clay. 
SOILS FAVORABLE FOR THE BALDWIN. 
If soils are thought of as grading from heavy to light, corres- 
ponding to the range from clay to sand, then soils grading from 
