The Yale expositor., 1915-08-26

dairy between Michigan and Wisconsin. The
numerous falls and rapids throughout its course
are being rapidly developed for power The
other important rivers are the Escanaba. White
Fish, Manistique, Carp, Pine, Tequamenon, Stur-
geon and Ontonagon.
Under the limitations of space imposed
this article il will be impossible to give even
brief description of the various types Of soil
which occur in Michigan. / shall therefore con-
line my remarks on this subject to brief state
ment regarding the proper of the general
soil maps of Michigan issued by the immigration
department.
These soil maps are the expression of an effort
to adapt the results of a careful scientific study
and mapping of the surface formations Of the
state to a distinctly unitarian purpose They
will be found useful to persons interested in OBJ
tanning a knowledge of the character and distri-
button of the soils in Michigan.
1t is known by everyone who has only slight
familiarity with soils that maps which show de-
tails Of soil composition and texture do not exist
and in the very nature of the cannot be
made There is no limitation OF subdivisions
that might be made soils to be classified
the basis of slight differences in physical and
chemical composition. On a single section OF
land there may be found one, two. SIX or a
dozen different kinds of SOIL depending the
basis of classification and the degree of i'm
portance attached to minor variations in char
acter On the soil maps referred to above there
shown in color and symbol IA types and
subtypes Of soil formations 1t is be-
leved that this degree of subdivision expresses
admirably the general facts. The character and
relations of these types and subtypes may be
readily understood and the number is not so
great to be confusing to the general reader
or layman.
While single small of land may show
wide variations in soil character, the number of
soil types depending. as stated above, on the i'm
portance attached to slight variations in charac-
ter, IL is not less true that the same may
have a great predomnance of soil of particular
character and composition, depending on origin
and manner of formation, and the general soil
conditions in such an area could be properly rep
resented on ii small-scale map by single color or
symbol The colors and symbols on the maps
press dominance in various areas covered by them
of particular soil OF the general character set
forth in the legend and not the entire exclusion
of other types. In the mapping of the soil forma
lions II should be understood that no attempt has
been made to measure general fertility or the
crop-growing capacity of the soil formations
particular crop adaptations to particular soils.
Soil fertility is thing which cannot be ex-
pressed on map. Local conditions of tempera-
ture, moisture, topography, physical and chemical
composition, the property of supporting bacterial
life, the character of the sub-soil etc, are i'm
portant determinants of crop-growing capacity
and 1t follows that this being true relative crop
growing capacity cannot be expressed on a soil
map. Particular kinds of soil under certain com
binations of the above factors will grow excellent
crops of particular kinds when other crops will
fail, wholly partially In these days OF spe
cialized farming practically every kind OF soil
can be managed In such a manner as to grow
remuneratiye crops, and soil management is a
factor in crop growing Of Importance equivalent