Soil Survey

Introduction

Soil is essential to human survival. We rely on it for the production of food, fibre, timber and energy crops. Together with climate, the soil determines which crops can be grown, where, and how much they will yield. In addition to supporting our agricultural needs, we rely on the soil to regulate the flow of rainwater and to act as a filter for drinking water. With such a tremendously important role, it is imperative that we manage our soils for their long-term productivity, sustainability and health.

The first step in sustainable soil management is ensuring that the soil will support the land use activity. For example, only the better agricultural soils in Manitoba will support grain and vegetable production, while more marginal agricultural soils will support forage and pasture-based production. For this reason, agricultural development should only occur in areas where the soil resource will support the agricultural activity. The only way to do this is to understand the soil resource that is available. Soil survey information is the key to understanding the soil resource.

Soil survey is an inventory of the properties of the soil (such as texture, internal drainage, parent material, depth to groundwater, topography, degree of erosion, stoniness, pH, and salinity) and their spatial distribution over a landscape. Soils are grouped into similar types and their boundaries are delineated on a map. Each soil type has a unique set of physical, chemical and mineralogical characteristics and has similar reactions to use and management. The information assembled in a soil survey can be used to predict or estimate the potentials and limitations of the soils' behaviour under different uses. As such, soil surveys can be used to plan the development of new lands or to evaluate the conversion of land to new uses. Soil surveys also provide insight into the kind and intensity of land management that will be needed.

History and Use of Soil Surveys in Manitoba

Reconnaissance, or small-scale, soil surveys were started in 1926 in Manitoba as the first step in the development of a basic program of soil research, education, conservation and use for the province. The first reconnaissance soil survey for Manitoba was published in 1940 for the south western area. It was at a small-scale of 1:126,000 or ½ inch to 1 mile. Although reconnaissance soil surveys have improved with aerial photography and interpretation since the 1940s, these maps are still based on only a small number of site investigations per section of land (approximately 6 inspections per 640 acres) and the soil map units identify only the dominant soil groups. The first large-scale, or detailed, soil survey in Manitoba was published in 1972 for the Portage la Prairie area at a scale of 1:20,000. Detailed soil surveys identify more of the variation in soil types across smaller landscapes. Detailed soil survey maps are much more accurate and reliable for making decisions at the farm-level.  They are created from much more intensive site investigations ranging from 16 to 30 per section of land.

The recent intensification of agriculture, coupled with serious water quality issues throughout North America, has increased the public's concern about agriculture's management of chemicals, fertilizers and livestock manure. In response to the public’s concern, there are many new initiatives being developed in Manitoba that use soil survey information to direct on-farm management practices. These activities include:

  • Environmental Farm Planning
  • Manure Management Planning
  • Nutrient Management Planning
  • Precision Farming
  • Watershed Management Planning
  • Land Use Planning

The success of many of these activities will depend on the availability of reliable, detailed soil survey information upon which the on-farm decisions are made. Unfortunately, currently only about 30% of agro-Manitoba has detailed soil survey. Essentially, there is virtually no detailed soil survey information for the Northwest region and very little for the Eastern-Interlake Region. Approximately 3/4 of the Central Region has detailed soil survey and approximately 1/3 of the Southwest Region. In many instances, when detailed soil survey information is not available, it is substituted with reconnaissance level information. Unfortunately, reconnaissance soil survey data is not reliable enough for making on-farm management decisions.

What are Soil Survey Reports? (Soil Management Guide)

How to Use a Soil Survey Report (Soil Management Guide)

Why is Map Scale Important? (Soil Management Guide)

What are the Limitations and Issues of a Map?

Soil survey maps are not without limitations. Although the map may say that a discrete area of land contains a certain soil type, it must be understood that the reliability of that information is a function of the map scale. All soil delineations (called polygons) contain small areas of dissimilar soils that are not identified (called inclusions). The smaller the scale of the map (or the more general the map), the more frequently this occurs. Small-scale, reconnaissance or general soil surveys give only a broad picture of the dominant types and distribution of soils that occur over relatively large areas. The landscape may actually include fairly significant areas of different soils that are not identified on the map. As such, reconnaissance soil surveys are best suited to making general comparisons of soil capabilities and limitations on a regional, national or even worldwide scale. They are not reliable for making on-farm decisions as they lack the detail necessary to describe the variation in the soil types on the farm.

In addition to the limitations of map scale, the boundaries of the soil map polygons imply there are abrupt changes in soil types within the landscape. In reality, however, soil varies continuously across the landscape. It must be recognized that, although the map lines imply abrupt changes, the soil grades from one type to the next and the lines on the map are only approximations of where these transitions occur.

The limitations of soil survey were summarized very simply by Hubert Byrd (Soil Survey Horizons) when he wrote:

"It is nature which controls the areal variability of soils, not soil scientists"

Similarly, it can be stated that it is nature which controls the areal variability of soils, not maps.

When detailed soil survey data is needed but unavailable, on-site investigations are necessary. On-farm soil survey can be designed for a specific purpose or general purpose. A specific or single purpose survey may be appropriate when there is only one, well-defined objective (such as siting a livestock operation). In this instance, only the information required to meet the single objective may need to be collected. The major advantage to a single purpose survey is decreased cost. A general-purpose survey, on the other hand, contains a wider range of information. Although more information is more costly to collect, the general-purpose soil survey may have more value over the long-term as it can be interpreted in a variety of ways and can be reused for many purposes.

Whether for a single or general purpose, soil survey begins with field inspections to a depth of approximately 1 meter and collecting information about the physical, chemical and biological properties of the soil. Differences in soil colour, texture and pH within the soil profile are then related to the surrounding landscape in order to determine soil type and predict behaviour. The reliability of the field data and its interpretation is largely dependent on the experience and ability of the surveyor. As soil survey expertise is scarce, data collection by less experienced individuals should always follow standardized procedures and should only be carried out by those who have received training in soil survey.

Soil Survey in Manitoba

Reconnaissance Soil Survey Reports

Reconnaissance Soil Survey reports provide a systematic inventory of Manitoba's soil resource at a scale of 1:100 000, 1:126 720 and 1:125 000. A report consists of a coloured map which indicates the distribution and area of soil map units and a report which provides a general description of the surveyed area, physical features, factors affecting soil development and an evaluation of the soil's agricultural, engineering and urban uses.
Click to enlarge
Report No. Project Name Scale Date Printed/Status
2 Armstrong   1939
3 South Western 1:126 720 1940
4 South Central 1:126 720 1943
5 Winnipeg-Morris 1:126 720 1953
6 Rossburn-Virden 1:126 720 1956
7 Carberry 1:126 720 1957
8 West-Lake 1:126 720 1958
9 Grandview 1:126 720 1957
10 Nelson River Basin 1:100 000 1959
11 Pasquia 1:63 360 1960
12 Fisher-Teulon 1:100 000 1961
13 Swan River1 1:126 720 1926
14 South Eastern 1:126 720 1964
15 Lac du Bonnet 1:126 720 1967
16 Grahamdale 1:126 720 1971
19 Red Rose-Washow Bay 1:126 720 1975
21 Ste Rose du Lac 1:125 000 1981
22 The Pas 1:125 000 1982
23 Waterhen 1:125 000 1985
R18 Swan Lake2 1:125 000 1996
R20 Grand Rapids2 1:125 000 1984
R21 Cormorant2 1:125 000 1975
R22 Wekusko2 1:125 000 data
R23 Pointe du Bois2 1:125 000 data
R25 Red Deer Lake3 1:34 860 1966
R26 Cross Lake-Norway House2 1:125 000 data
R28 Soils and Salinity Conditions in the Pasquia Lake Area 1:50 000 1984
R29 Duck Mountain Forest Reserve2 1:125 000 data

1Map area with R18, Swan Lake
2Map/data available
3Report/Map available

Biophysical Land Classification Reports

A system of inventory known as a "biophysical land classification" was used to describe various land attributes such as a soil, surficial deposits, landforms, permafrost and water in northern and eastern Manitoba. Interpretation of this basic information for environmental sensitivity, capability for wildlife, forestry, recreation etc. is possible by relating it to more dynamic features such as vegetation and wildlife populations within an overall climatic framework.
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Report No. Project Name Scale Date Printed/Status
B1 Lake Winnipeg, Churchill and Nelson River 1:250 000, 1:50 000 1973
B2 Churchill Transportation Corridor 1:125 000 data
B3 Hayes River, 54C 1:125 000 1976
B4 Kettle Rapids, 54D 1:125 000 1976
77-3 Hecla, 62P-Carroll Lake, 52M 1:125 000 1977
78-1 Bernes River, 63A-Deer Lake, 53D 1:125 000 1978
78-2 Knee Lake, 53M 1:125 000 1978
78-7 Oxford House, 53L 1:125 000 1978
79-2 Sipiwesk Lake, 63P-Split Lake, SE - 64A 1:125 000 1979
B10 Island Lake, 53E 1:125 000 data
B11 Norway House, 63H 1:125 000 data

Detailed Soil Survey

Detail Soil Reports (1:20 000, 1:40 000, 1:50 000) provide detailed and comprehensive soil resource information to supplement and expand on information contained in the Reconnaissance soil survey reports. As well as basic soil information, a variety of derived and interpretive maps can be generated including Soil Suitability for Agriculture, Soil Suitability for Irrigation, Drainage, Salinity, Potential Impact of Irrigation.

The two concepts of "intensity of mapping" and "map scale" refer to different but closely related aspects of a soil survey. The Survey Intensity Level (SIL) is defined by the number of field inspections per unit area. Survey Intensity Levels range from SIL1 (very detailed) to SIL5 (exploratory in nature). Map scale is the scale of publication. In general an SIL1 relates to 1:5,000 map scale, an SIL3 relates to a 1:20,000 to 1:50,000 map scale and an SIL5 related to a 1:100,000 or smaller map scale. The provincial soil survey program places the emphasis on map scale in its program. Field inspection sites for a 1:20,000 map scale (3.2 inches to 1 mile) requires 25-30 inspection sites per section of land and a 1:50,000 map scale (1.5 inches to 1 mile) requires 16 inspections per section. A two-person crew usually maps one section per day.

The steps involved in organizing a detailed soil survey at 1:20,000 map scale are:

Preplanning

  • Review all existing background information for the area to be surveyed. This includes reconnaissance and/or detailed soil reports, elevation maps, NTS maps, and aerial photos. The geological information about the surveying region should also be included. NTS maps and aerial photos can be used to assess the accessibility of each section to be surveyed. Using twin air photos viewed with stereo glasses or software like PurView delineate landform boundaries. Draft soil polygons and soil observation sites can be identified.

Group correlation

  • Landscape and topography are reviewed and representative sites for field inspection and soil polygon delineation are selected. The description of the soil profile must be described by all surveyors in an accurate and consistent manner to ensure that the same soil is being classified as the same series by all surveyors.

Field surveying Typical soil sampling and inspection pattern for a detailed soil survey

  • Investigate soil variability within landforms by soil sampling to a depth of at least 3 feet (1 meter) at regular intervals along transects. (It is preferable to georeference these inspection sites using GPS technology). Inspections are conducted every 1/4 mile (400 metres) around the perimeter of a section and every 1/8 mile (200 metres) along two transects at the 1/4 mile (400 metres) and 3/4 mile (1200 metres) points of the section, for a total of 30 sites (see right). Classify soils in the field visually using standardized criteria for texture, colour, presence of carbonates, presence of mottles, and type of parent material and landscape position. This information will assist in determining what soil horizons are present, which in turn will identify the soil series and phase present in each map unit.
  • Record any changes (land use, drainage improvement, etc.) between images and onsite observations. Polygons are verified on mylar based on site inspections. Field tests of soil texture and calcareous reaction with are regularly verified with reference samples. Soil samples from different horizons are collected while minimizing contaminations. Soil samples must represent all soil series observed. Any unusual findings are discussed at regular onsite meetings.
  • In order to maintain a database of soil properties such as texture, pH, carbonate content and salinity throughout different areas of the province, samples are taken from daily sites for analysis. Random surface and subsurface samples should be taken to quantify these properties.
  • At a 1:50000 scale approximately 2 inspection sites per section will be sampled — 2-3 horizons per site = Approximately 5 samples per section (180 samples per township) Approximately 10 samples per section (360 samples per township) at a 1:20,000 map scale.
  • Lab analyses also aid soil surveyors by confirming soil texture or carbonate levels and these are in addition to the random sampling mentioned above. Soil series should also be considered when the samples are taken so that most soil series will have lab data for verification of characteristic properties.

Methods of Soil Analysis, Parts 1 and 2, and Carter (1993) can be referred for the following soil properties. Laboratory analyses of the following factors are conducted in order to verify field data for proper soil horizon classification: (Olson, 1984, p.22):

  1. particle size (texture) - pipette method
  2. bulk density
  3. water retention
  4. cation exchange capacity
  5. base saturation
  6. sodium adsorption ratio (SAR)
  7. organic carbon
  8. calcium carbonate, gypsum
  9. N, P, K, S, Ca, Mg, Na, Fe, Al, NO3-, CO3-2, HCO3-, Cl-, SO4-2 using atomic absorption and/or ion specific electrode analyses
  10. electrical conductivity (EC) from the saturated paste method
  11. pH (in CaCl2)

Soil polygon delineation

  • Refine map units and soil boundaries from field descriptions, laboratory data and variability observations.
  • Verify soil classifications by recording all pertinent data, reviewing field and laboratory data, re-examining stereo photographs and consulting with experienced pedologists.
  • Draw lines to indicate the soil boundaries and include soil symbols on the air photos or base map. Write soil map unit descriptions.
  • The considerations for drawing soil polygons should include the following:
    • Map scale: this affects the appropriate number of soil polygons per unit area.
    • Polygon size: the minimum polygon size should be appropriate for the map scale. As a general rule, the smallest soil polygon on any scale of map should be larger than 0.5 cm2, for allowing map unit symbols to be legible, unless for strongly contrasting units.
    • Landscape, topography, soil drainage, soil parent materials/soil series, differentiating contrasting features such as water bodies, bushes, and forest.
    • Using natural features such as water courses as polygon boundaries.
    • Using updated and best representing images and other available supporting feature layers.
    • Considering previous soil maps and polygon boundaries if available.
  • Digitizing of fixed features such as streams or water bodies should take place while zoomed in to 1:2,000 to 1:5,000 for 1:50,000 maps and 1:1000 to 1:3,000 for 1:20,000 maps. Other resources for imagery to compare to PurVIEW include: air photo hard copies, air photo mosaics, and Google Earth.
  • Manitoba Soil Survey Field Procedures Manual (PDF 2.17 MB)
  • Manitoba Soil Survey Laboratory Procedures Manual (PDF 421 KB)

 

Detailed Soil Survey Maps and Reports

Project No. Project Name Scale Date Printed/Status
17 Portage la Prairie 1:20 000 1972
18 Morden-Winkler 1:20 000 1973
20 Boissevain-Melita 1:20 000; 1:40 000 1978
29 Winnipeg Region (D14) 1:20 000 1975
30 Brandon Region (D15) 1:20 000 1976
D13 LGD Alexander-Organic Soil Study 1:63 360 1975
D17 Roseau River-Organic Soil Study 1:20 000 1977
D19 Pelican-Rock Lake 1:20 000 1983
D20 West Portage-MacGregor 1:20 000 1982
D21 Lake Minnewasta 1:20 000 1978
D22 Killarney 1:20 000 1979
D23 Matlock-Gimli-Riverton 1:20 000 1981
D24 Glenboro 1:20 000 1979
D25 Sandy Lake 1:20 000 1980
D26 Brokenhead 1:20 000 1979
D27 Rockwood 1:20 000 1980
D28 Oak Lake 1:20 000 1979
D29,30 Bird River-Lac du Bonnet 1:20 000 1980
D31 Grindstone Point 1:20 000 1979
D32 Paint Lake 1:10 000 1980
D33 Cranberry Portage 1:5 000 1980
D34 Dauphin 1:20 000 1981
D35 South Riding Mountain Planning District 1:20 000 1990
D36 West Interlake 1:20 000 1981
D37 Swan River 1:20 000 1987
D38 Hadashville Organic 1:20 000 1981
D40 Falcon Lake, West Hawk, Brereton, Jessica Lake Areas 1:20 000 data
D41 Quesnel Lake, Winnipeg River Area 1:20 000 data
D42 Duck Mountain 1:20 000 1982
D43 Spruce Woods E.L.C. 1:40 000 data
D45 Pine Creek 1:20 000 1983
D46 Arborg-Riverton 1:20 000 1982
D47 Roblin 1:20 000 1983
D48 Flin Flon 1:20 000 1989
D49 RM's of Ste Anne, La Broquerie and part of GD Stuartburn 1:50 000 1985
D50 City of Brandon 1:20 000 1984
D51 Westbourne 1:20 000 1985
D52 Rathwell, Treherne, Notre Dame 1:20 000 1984
D53 Altona, Emerson, Gretna, Ile des Chenes, Landmark, Letellier, Rosenort, St. Jean 1:20 000 1984
D54 Russell-Binscarth 1:20 000 1985
D55 Ste. Rose du Lac 1:20 000 1985
D56 Souris, Wawanesa, Virden 1:20 000 1986
D57 Fraserwood, Inwood, Komarno 1:20 000 1986
D58 Hallboro-Neepawa 1:20 000 1984
D59 Beaudry Park 1:20 000 1986
D60 RM's of Dufferin, Grey, Roland, Thompson and part of Stanley

1:20 000; 1:50 000

1988
D61 Meditation Lake, Wanipigow Lake Areas 1:20 000 data
D62 Wanipigow Lake 1:20 000 data
D63 Shellmouth Reservoir North 1:20 000 1987
D64 South Assiniboine River 1:20 000 1987
D65 Birtle, Elkhorn, Hamiota, Newdale, Rapid City, Shoal Lake, Strathclair 1:20 000 1987
D66 Benito-Durbin 1:50 000 data
D67 St. Eustache, Springstein, Perimeter Strip, Brunkild, La Salle River 1:20 000 1989
D68 Spruce Point Mine 1:10 000 1985
D69 Snow Lake 1:20 000 1985
D70 Lorne RM 1:50 000 1987
D71 Whitemouth Peatland 1:50 000 1987
D73 Victoria Beach-Elk Island 1:20 000 1990
D74 South Norfolk

1:20 000; 1:50 000

1987
D75 Victoria RM 1:20 000 1989
D76 Rhineland RM 1:20 000 1991
D77 Pembina RM 1:50 000 1993
D80 Norfolk RM 1:20 000 1991
D81 Plum Lakes Project 1:20 000 1991
D82 Hanover RM 1:50 000 1993
D83 Louise RM 1:50 000 1998
D84 Argyle RM 1:50 000 1997
D85 North Cypress RM 1:20 000 1999
D86 Strathcona RM 1:50 000 1999
D88 Springfield 1:20 000 2011
D89 Ritchot 1:20 000 2011
D90 Killarney-Turtle Mountain 1:50 000 2011
D91 Blanshard 1:50 000 2011
D92 Roblin 1:50 000 2013
D93 Hamiota 1:50 000 2013

 

Several intensive soil surveys (1:5 000) have been carried out on smaller sites with the purpose of describing the soil conditions in sufficient detail to assist in planning and managing the soil resources in support of specific research purposes.

Report No. Special Soil Resource Products
93-1 Soils of the Carman Research Station N½ Sec23-Tp6-Rge5W 1:5 000 map and report
94-1 Minor Element Content of Agricultural Soils in Manitoba
94-2 Geomorphology and Soil Quality of the Twin Watershed Area and Project
94-3 Soils of the Manitoba Zero Tillage Research Association Research Farm Sec31-Tp12-Rge18W 1:5 000 map and report
95-1 Soils of the Manitoba Crop Diversification Centre S½ Sec8-Tp11-Rge14W 1:5 000 map and report
96-1 Soils of the Roblin Effluent Irrigation Site NE¼ 20-Tp25-Rge28W 1:5 000 map and report
96-3 Water Erosion Studies in Manitoba - A Status Assessment
97-1 Soils of the S½ of N½ Sec3-Tp3-Rge5W Morden MB
97-2 Unified Soil Classification System for Engineering Applications 1:2 000 000 map and report
99-1 Soils of SE32-14-25W, Miniota Precision Agriculture Research Site 1:5 000
99-2 Soils of the Brandon Research Centre
99-3 Soils of 32-09-19W, Research Plot Sites, Brandon Research Centre
5242/B Soil Landscape Map of Manitoba 1:1 000 000 map and legend
5257/B Wind Erosion Risk Map of Manitoba 1:1 000 000 map and legend
5259/B Water Erosion Risk Map of Manitoba 1:1 000 000 map and legend
5261/B Soil Salinity Map of Manitoba 1:1 000 000 map and legend
The Soils of Manitoba
Soil Survey of the Morden Experimental Farm, Morden
The Soils of Deep Lake Study Area
Soil Map of the Onanole Study Area - Portions of Tp 19 Rges 18 and 19W
Glenlea Research Station - Lots 2 to 9 inc - Parish of St Norbert Tp 8 Rge 3E

 

The Description of Soil Series in Manitoba (PDF 1.33 MB)

Why are Detailed Soil Survey Reports Required for In-Field Assessments? (Soil Management Guide)

Options for data collection when detailed soil survey information is unavailable (Soil Management Guide)

The Geospatial Environment

Soil surveys have been published for all of Agro-Manitoba and for certain areas across Central and Northern Manitoba. Data from these surveys comprise the most detailed soil inventory information in the SoilAID (Soil Agricultural Interpretations Database) and SoilSMUF (Soil Map Unit File) GIS files which are available for download on the MLI (Manitoba Land Initiative) website. These files are the source of soil information on Agri-Maps, a web-based map viewing application. (Note: Registration is required to access the MLI. The designation of a User Name and Password is necessary to complete the free MLI registration. Registration is not required for use of Agri-Maps.)

The significant characteristics of detailed and reconnaissance soil surveys are as follows:

  • SCALE: For detailed soil survey, scale ranges from 1:20,000 to 1:50,000. For reconnaissance soil survey, scale ranges from 1:125,000 to 1:126,720. Scale can vary within one Rural Municipality (RM), depending on different surveys conducted at different times and different scales in different portions of an RM. Note: Some smaller project areas were surveyed at a scale of 1:5,000; however, not all of these files have been digitized to GIS files.
  • COVERAGE: Coverage consists of 119 individual RMs mainly of the significant agricultural areas. For specific coverage, see the SoilAID and SoilSMUF.
  • SYMBOLIZATION: Within survey projects symbolization and legend is consistent and correlated between map sheets. Map symbols and the associated information are located in the SoilAID Description and SoilSMUF Description files.
  • CORRELATION: Some map edges may not have been matched to computer tolerances and therefore inconsistencies may exist between RMs in terms of symbolization. This may result in an imperfect correlation when seaming data across RM boundaries.
  • ATTRIBUTES: For each polygon, the shapefile (.shp) attribute table defines up to three soils/non-soils (Field = MAPUNITNOM), in addition to an estimate of the proportion of each soil/non-soil within the polygon (Fields = EXTENT1, EXTENT2, EXTENT3). Soil association names in Reconnaissance GIS files have been translated to soil series names in the MAPUNITNOM Field.

Dataset descriptions

The following data categories are used as references for delineating polygons within the SoilAID and SoilSMUF files.

  1. Administrative Boundaries (RM, Section Files, Urban Areas)
  2. Hydrological Data
  3. Transportation Network Data
  4. Cadastral Data

Each SoilAID and SoilSMUF file contains a metadata file. An example is the metadata for the RM of Albert.

For further information, contact your MAFRI GO Office.