GUELPH, ONTARIO - Agriculture and Agri-Food Canada

Ao - Accu mulated
layer of partially
from deciduous trees.
decomposed litter
A1 - Dark grey to very dark grey mineralized layer.
G- Brownish grey, mot8tled mineral layer.
C- Greyish brown parent material.
The Bog soils consist of organic accumulation one to three feet and more
in depth. They may differ according to the degree of decomposition of the
organic materials from which the soils have developed. The well decomposed
dark Bog soils are referred to as “Muck” and the poorly decomposed organic
materials as “Peat.” The Bog soils have formed under very poorly drained
conditions and frequently occupy depressional areas which receive considerable
seepage.
The Alluvial soils consist of recently deposited material which has not been
in place long enough for definite soil horizons to develop. However, layers
differing in texture as a result of periodic flooding, can frequently be observed
in the profile of these young alluvial soils.
The Dry Sands consist of sandy material of recent deposition which has
not been exposed to soil forming processes long enough for profile characteristics
to develop. The soils in tlhe group are essentially loose sands with excessive
drainage.
System
of Classification
On the basis of their differentiating characteristics soils are grouped into
categories which can be described and’ readily recognized. The three categories
commonly used in mapping soils are series, type, and phase. .
The soil series is a group of soils with genetic horizons similar in differentiating
characteristics and arrangement in the soil profile and developed from a
particular type of parent material. Except for texture, particularly in the
X1 horizon, the physical character and thickness of the horizons do not vary
significantly within a series. Such characteristics include colour, structure,
organic matter content, reaction, and texture.
The soil type is the principal unit of mapping and is most specific in character.
The soil type name consists of a series name plus the textural class
name derived principally from the texture of the A1 horizon. Although the
soil type unit is the most specific unit recognized in mapping soils it should be
pointed out that it includes a range of conditions. The profile descriptions
presented in the report do not represent a specific location but cover the average
conditions most commonly found in the particular area. With mapping done
on the scale of one inch to the mile it is often necessary to include small areas
of other related soils in a delineated area with t,he dominant mapping unit.
The variability within a mapping unit varies in the soil series. The range of
characteristics tolerated within a series is discussed under the description of
the various series.
32