Soil Report - Agriculture et Agroalimentaire Canada

Soil profile descriptions taken from the survey of the
Haldimand-Norfolk Region were compared to the generalized
profile descriptions illustrated on Figure 46 . Examples were
found of all groups except group S-5 . Individual soil series of
the Haldimand-Norfolk Region were assigned toone of the eight
drainage groups represented . The group for each series is
identified by the first two symbols ofthe drainage code given
in Table 28 . An example is the Haldimand soil for which the
drainage code is SIIH4 . The first two symbols, S1, indicate
that the Haldimand soil is assigned to the drainage group S-1 .
(c) Source of Excess Water in the Soil Profile
Interpretation of the principal source of excess water in
the soil profile was based upon the European concepts for
surface water gleysols and groundwater gleysols . Surface
water gleysols are soils in which the principal source of
excess soil water is interpreted to be surface water . Groundwater
is interpreted to be the principal source of excess soil
water in groundwater gleysols .
Robson and Thomasson (43) propose the following
definitions for surface water gleys and groundwater gleys .
"Surface water soils occur where the downward movement
of water is restricted by an impermeable or slowly permeable
layer in sites remote from a regional groundwater
table . This layer usually was related to inherent lithological
features or a result of soil-forming processes such as a
Bt horizon of translocated clay" (surface water gleys) .
"Groundwater soils occur where waterlogging is mainly a
result of proximity to a groundwater table" (groundwater
gleys) .
In relation to Robson and Thomasson's definitions, Table
29 gives three soil characteristics used to differentiate
between drainage groups . For each drainage group, the
column headed "General description and criteria" gives
general textural class and family particle size class for the
profile and soil structure of the least permeable horizon in
the upper metre of the profile . The depth of one metre was
chosen as it includes conventional depths for installation of
buried drainage pipes .
By the criteria noted, Haldimand-Norfolk Region soils
grouped in drainage groups S-1 through S-6 inclusive, are
interpreted to contain slowly permeable horizons within the
upper metre of the profile, in locations well above a regional
groundwater system but subject to soil saturation by perched
groundwater at depths of a metre or less . In such soils, the
principal source of excess soil water is interpreted to be
surface water . This interpretation is applied to an individual
soil listed in Table 28 by the first symbol, S, in the drainage
code for the soil, e.g . S3IH4. The symbol S stands for the
surface water gleysol .
By the three criteria used to differentiate drainage groups,
each of the groups G-1, G-2 and G-3 is represented in
Haldimand-Norfolk Region soils . These soils are interpreted
to contain soil material deeper than one metre that provides
moderate to high rates of internal drainage, with necessary
drainage works in place. Without appropriate drainage
works, and during periods of high groundwater table, relief
of soil saturation is dependent upon natural controls on the
rate of groundwater movement . In such soils, the principal
source of excess soil water is interpreted to be groundwater .
This intepretation is applied to individual soils listed in
Table 28 by the symbol, G, in the drainage code for the soil,
e.g . G2IJ4 . The symbol G stands for groundwater gleysol.
(d) Landform andLand Slope
The fourth and fifth symbol of the drainage code assigned
to individual soils, in Table 28, represent landform and
slope, respectively. For the Brady series the complete code
89
is G21J4, in which J stands for level to undulating landform,
and the fifth symbol, 4, stands for slope range of 0.5-5% .
The landform and slope designations given in Table 28
are based upon standard landform and slope classes given in
The Canadian System of Soil Classification (21) . However, in
some instances, the range of landform and slope parameters
observed during field survey of individual soil series, included
more than one of the standard classes . To represent ranges
in parametrs found during soil survey, combinations of
standard landform and slope classes were used . Combinations
assigned to individual soil series of the Haldimand-Norfolk
Region are taken from Tables 30 and 31 which were
developed during original interpretation of the nine drainage
groups shown on Figure 46 .
Table 30. Drainage code landform classes
Code symbol
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
a
b
Landform
level
level, dissected
level to inclined, dissected
level, complex
level, terraced
level, midslope terraced
level to inclined
level to undulating
level to undulating, midslope
level to undulating, midslope terraced
undulating
undulating, dissected midslope
undulating, midslope
undulating, ridged
inclined
inclined, midslope
inclined to undulating, terraced
inclined, dissected
inclined to hummocky
undulating to rolling
undulating to rolling, dissected
hummocky
hummocky, ridged
rolling
rolling, dissected
rolling, ridged
terraced, dissected
undulating to inclined, midslope,
complex dissected