GLO Soil Classification
General Land Office Research
Department of Landscape Architecture
Iowa State University
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From 1832 to 1859, the General Land Office (GLO) conducted the original public land survey of Iowa. Deputy Surveyors were required to describe the soils along each mile they surveyed as 1st rate, 2nd rate, or 3rd rate. Because these terms were not defined by the GLO, GIS descriptive modeling was used to help describe areas with 1st rate soils, areas with 2nd rate soils, and areas with 3rd rate soils. Hypotheses that guided the research stated that (a) the historic GLO classification of soil suitability for agriculture in Iowa is different than the modern USDA classification and (2) the GLO soils classification rated areas near river valleys as high suitability for agriculture, especially terrace positions and upland positions, areas near timber resources, and areas with well-drained soils.
Evidence developed in this research supports the first hypothesis. In the study area (Franklin Township, T80N, R22W, Polk County, Iowa), the most productive areas (by modern standards) were described by Evans in September, 1847, as 3rd rate and the least productive areas were described as 1st rate. The poorly drained pothole soils of the 3rd rate area presented an obstacle to pioneer agriculture not removed by drainage technology until a half century later. Perhaps the lack of timber and water also made the 3rd rate area unsuitable in Evans' view. Evidence developed in this research partially supports the second hypothesis. In Franklin Township, 1st rate soils were relatively close to timber, groves, and the South Skunk River. However, 1st rate soils were located somewhat in upland areas, but primarily in floodplain areas. Also, 1st rate soils were located in areas with a range of drainage characteristics: poorly-, moderately-, and well-drained. The seven fields mapped by Evans seem quite suitable for agriculture by both GLO standards and modern standards. All were located in 1st rate areas, close to timber and grove. The fields ranked relatively high in all three modern measures of agricultural suitability (CSR, ECY, and USDA Prime Farmlands). The first 14 parcels sold to 5 buyers at the GLO land office (on October 30, 1848) have characteristics quite similar to the seven fields, with two exceptions: (1) the first parcels sold have a much higher mean slope than the fields and (2) the first parcels sold have a much lower mean CSR and mean ECY than the fields. The 26 farmsteads mapped in the Andreas Atlas of Iowa (1875) have characteristics similar to 1st rate soils and 2nd rate soils, indicating less dependence on timber and river resources than the first parcels sold.
In a review of field notes for townships throughout Iowa, Deputy Surveyors often commented favorably on soils that were rich and well-drained, timber that was sufficient and convenient, water of a lasting character, and bottoms that were luxuriant and handsome. They also described areas unfit for cultivation: swamp land with numerous ponds and marshes, hilly land that was broken and steep, gravelly soil that was cold and sterile, water that was sluggish or eternally muddy, and inferior timber that was destitute and second rate. The settler and speculator land buying criteria examined in the literature indicate diversity rather than singular agreement. Criteria were influenced by previous farming experiences, cultural background, type of land available for purchase, timing, transportation, technology, and strategies for dealing with needs (such as wood and water) and obstacles (such as potholes and other wetlands). The greatest limitation of these GIS modeling results is that they apply to only one township in Iowa. More research is needed to broaden the geographic scope and the depth of the related literature. The following recommendations help to provide more research evidence that specifically addresses the hypotheses:
Below are links to further description and results of the research:
The GLO Surveyor General required Deputy Surveyors to record information about the landscape as they surveyed each section line in Iowa. Among the information were soil ratings: first rate, second rate, and third rate. The soil ratings in their notes provide an interesting look at what the Surveyors called the "face of the country." The survey maps and notes produced by the GLO surveyors are among the few detailed, systematic data sources about Iowa before much of it was changed to a landscape of intensive agriculture.
For each mile of section line, deputy surveyors were required to record distances (in chains and links) between section corners and quarter corners. Along the section lines, they also noted distances from section corners to landscape features (such as streams, escarpments, rock outcrops, line trees, and timber stands) and cultural features (such as cabins, fields, and trails). Sometimes, width or other dimensions of the features were recorded in the field notes. At section corners, surveyors listed the common name, distance and direction to at least two witness or bearing trees (if there were any within a reasonable distance). For each mile of section line, surveyors summarized the predominant vegetation and rated the soils (first rate, second rate, or third rate).
Deputy surveyors described these landscape features in their field notes, written in leather-bound field books. In the 1851 General Instructions to Deputy Surveyors, the Surveyor General stated the purpose of field notes succinctly: "Your field notes are to form a full and perfect history of your operations in the field." The Surveyor General expanded his description of field notes in the 1855 General Instructions to Deputy Surveyors:
The field notes afford the elements from which the plats and calculations in relation to the public surveys are made. They are the sources wherefrom the description and evidence of locations and boundaries are officially delineated and set forth. They therefore must be a faithful, distinct and minute record of everything officially done and observed by the surveyor and his assistants, pursuant to instructions, in relation to running, measuring, and marking lines, establishing boundary corners, &c; and present, so far as possible, a full and complete topographical description of the country surveyed, as to every other matter of useful information, or likely to gratify public curiosity. The description of the surface, soil, minerals, timber, undergrowth, &c., on each mile of line, is to follow the notes of survey of such line.
Items 5, 7, 8, and 10 of the Surveyor General's 1855 General Instructions to Deputy Surveyors provided only minimal guidance in describing the soils, their landscape position, and drainage characteristics:
5. Intersections by line of land objects. The distance at which the line first intersects and then leaves every settlers claim and improvement; prairie, river, creek or other “bottom”; or swamp, marsh, grove, and windfall, with the course of the same at both points of intersection; also the distances at which you begin to ascend, arrive at the top, begin to descend and reach the foot of all remarkable hills and ridges, with their courses, and estimated height, in feet, above the level land of the surrounding country, or above the bottom lands, ravines, or waters near which they are situated.
7. The land’s Surface - Whether level, rolling, broken, or hilly.
8. The soil - Whether first, second, or third rate.
10. Bottom lands - To be described as wet or dry, and if the subject to inundation, state to what depth.
In a previous edition, items 21 and 22 of the Surveyor General's 1850 General Instructions to Deputy Surveyors provided slightly different guidance in describing soils and the landscape:
21. The face of the country, whether level, rolling, broken, hilly, or mountainous.
22. The quality and character of the soil, whether first, second, or third rate.
The General Instructions of 1846 and 1851 provide guidance similar to the 1855 General Instructions. However, the 1843 General Instructions were slightly different regarding descriptions of soils and the landscape:
At the end of every mile...you will give a particular description of the face of the country, whether level, hilly, or mountainous; of the quality or rate of the soil, whether 1st, 2nd, or 3rd rate, or unfit for cultivation, and if liable to inundation state to what depth; of the kinds and quality of the timber and undergrowth.
The 1834 General Instructions were similar to the 1843 instructions regarding descriptions of soils and the landscape:
At the end of every half mile...you will give a particular description of the face of the country, whether level, hilly, or mountainous; of the quality or rate of the soil, and whether it is fit or unfit for cultivation; and, particularly, whether the bottom land is liable to inundation or not; and, if it shall be liable to inundation, state, also, to what depth, so far as that circumstances may come to your knowledge, whether from observation or the water marks upon the tree, or any other source of information; and note the kinds and quality of timber and undergrowth, naming the different sorts in the order in which they predominate.
The General Instructions of 1834, 1843, 1846, 1850, 1851, and 1855 all were more specific than the 1831 instructions:
Ever surveyor shall note in his field book...the quality of the lands.
|To the left is an example of two
facing pages from field notes written by GLO deputy surveyor Perrin Kent.
The township he was surveying is identified as Tier 69 North and Range 07
West. This township would later become part of Lee County, Iowa (the
northwest corner of the county). Kent completed his survey of this
township on September 23, 1837 (a few days after he surveyed the section
lines described in the example field notes below).
Kent describes the line between sections 8 and 9 "Land Broken 2nd rate." The line between sections 4 and 9 is described as "Land on creek 2nd rate."
Excerpts from surveyors' field notes provide more examples of soil ratings and surveyors' interpretations of agricultural suitability.
The purpose of the land survey and recording information about the landscape was to aid in "disposal" of the land (Lokken 1942). In Iowa, "disposal" involved either selling land to Euro-American settlers or giving land to states, counties, schools, war veterans, railroads, steamboat companies, and others as rewards or economic incentives. For more information about GLO surveying methods in Iowa, Frequently Asked Questions. Also see Original Instructions Governing Public Land Surveys of Iowa (Iowa Engineering Society, Ames) by J.S. Dodds (1943) and Public Land Surveys: History, Instructions, Methods (Collegiate Press, Ames) by Lowell O. Stewart (1935).
2. Research hypotheses
The Surveyor General's Instructions did not include definitions or descriptions of first rate, second rate, or third rate soils. However, reading GLO field notes while working on previous research in historic vegetation provided insight into criteria the Deputy Surveyors may have used (Anderson 1996). The logical and spatial patterns observed in the previous research provided the basis for the following research hypotheses:
The soil rating criteria used by the Surveyors were a product of their education and work experience, particularly in agriculture. It is a reasonable assumption that many of the Surveyors had lived or worked on farms, giving them a first-hand basis on which to rate soil quality for agriculture. Without modern transportation facilities, commercially-available building materials, water well-drilling equipment, and drainage technology, the Surveyors of the mid-nineteenth century rated well-drained locations near river valleys as first rate soils.
3. Methods and materials
To test these research hypotheses, Geographic Information System (GIS) technology was used to describe areas with first rate soils, areas with second rate soils, and areas with third rate soils. GIS descriptive modeling was used to describe areas in terms of modern soil characteristics (such as slope, landscape position, drainage, and Corn Suitability Rating) and distance to features (such as rivers, river valleys, timber, and fields). GIS technology provides the tools to explore spatial relationships for hypothesis formulation and testing (DeMers 2002, p. 2).
Descriptive modeling helps answer questions about "what is where," and "how much is there," "what relationships are there." Descriptive modeling is based on the cartographic concept of map overlays and the statistical concepts of cross-tabulation and descriptive statistics. Each soil class (first rate, second rate, and third rate) was described according to the proportions in different slope classes, drainage classes, and other variables. The relationship between soil ratings and each of the variables was measured with Chi-square. Each soil class (first rate, second rate, and third rate) was also described according to the mean values for Corn Suitability Ratings, distance to river valleys, and other variables. GIS databases, software, and analytical functions provided the basis for spatial correlation of variables, yielding a spatial and statistical profile of areas with first rate soils, areas with second rate soils, and areas with third rate soils.
The study area selected to test the research hypotheses is one township in the northeast part of Polk County, Iowa: Tier 80 North, Range 22 West, 5th Principal Meridian. The study area is a standard 6-mile by 6-mile survey (Congressional) township. It covers the same area as Franklin Township, a civil township in Polk County. Part of the town of Bondurant is in the southwest corner of the township. US Highway 65 bisects the township southwest to northeast. According to 1992 land cover data from the US Geological Survey, 91 percent of the township was in agricultural use, 4 percent in tree cover, 2 percent in wetland, 2 percent in urban use, and 1 percent in water.
The study area is approximately 9,463 hectares (23,380 acres). It is located within the Des Moines Lobe landform region (Prior 1992). The edge (lateral moraine) of the Des Moines Lobe is approximately 3 miles to the east of the township.
The major natural feature in the township is the South Skunk River, which flows from northwest to southeast. The associated floodplain is from 2 to 3 miles wide in the study area. Chichaqua Wildlife Area is located on the floodplain in the north-central part of the township. This 3,000 acre area is owned and managed by the Polk County Conservation Board. It is located along the former meandered channel and oxbows of the Skunk River. It is now part of the Chichaqua Bottoms Greenbelt, which stretches for almost ten miles along the South Skunk River. Engeldinger Marsh, another Polk County Conservation area, is well known for its diversity of plant and animal species and is located in the northeast corner of the township.
Franklin Township (T80N R22W) was selected as the study area for GIS modeling for the following reasons:
Township T80N R22W was surveyed by GLO Deputy Surveyor John D. Evans from September 16 to 23, 1847. Evans was accompanied by two chainmen (John Wilson and George Howell), a marker (William Howell), and a flagman (C.A.R. Logan). Evans and his survey party surveyed 60 miles of section lines and walked at least 60 additional miles for a total of over 120 miles in 8 days, a pace of at least 15 miles per day. Evans surveyed a total of 19 townships in Iowa (2 in Polk, 9 in Jasper, 4 in Ringgold, and 4 in Taylor).
Franklin Township was part of the "New Purchase," the Sauk and Fox Cession of 1842 (Lokken 1942, p. 15), also called the Royce Cession 262 (Swierenga 1968, p. 18). However, because it was west of the "Temporary Indian Boundary 1843-1845" (Red Rock Line), this part of the cession was not available for settlers until midnight of October 11, 1845 (Pratt 1972, p. 61). Polk County was established and incorporated on April 22, 1846 (Pratt 1972, p. 62). Swierenga (1968, p. 231) reported that land in Franklin Township was first offered for sale in 1848. According to Pratt (1974, p. 66), Franklin Township was not organized as a civil (political) township until March 6, 1854.
|Land area sold in Franklin Township by the end of...||Percent sold|
|Source: Swierenga 1968, p. 234-237|
Because the Fort Des Moines Land Office was not established until 1852 (Swierenga 1968, p. 8) or 1853 (Pratt 1972, p. 65), the early land sales in Franklin Township were entered at the Iowa City land office (Union Historical Company 1880, p. 390).
The map of Polk County in the Andreas Atlas of Iowa (1875) shows the location of 26 early farmsteads in Franklin Township, each with a point symbol and the owner's name. One farmstead shown without a point symbol on the map (in section 29) was not included in the modeling.
The primary GIS modeling tools were ArcView 3.3 and the Spatial Analyst extension. The GIS database included soil themes and interpretive information from the Iowa Cooperative Soil Survey:
The GIS database included themes from the Iowa Department of Natural Resources Natural Resources Geographic Information System (NRGIS) library in ArcView format. NRGIS themes used in modeling included the following:
The GIS database included themes from the US Geological Survey:
The GIS database also included data from the General Land Office township plat maps and field notes. These were prepared in digital form by the author in previous research (Anderson 1996) or specifically for this research. They include the following:
The theme most central to the modeling was derived from the Public Land Survey System (PLSS) theme from NRGIS. Using information from the GLO Deputy Surveyor's field notes, several new fields were added to the PLSS attribute table:
4. Descriptive modeling of GLO data characteristics
Each of the four classes of soil ratings (1st rate, 2nd rate, 3rd rate, and not rated) can be described by measuring quantities and by examining relationships with other data characteristics described by Deputy Surveyor John Evans. These characteristics include the following:
Soil ratings. Deputy Surveyor Evans surveyed a total of 60 miles of section lines in Franklin Township. Soils in the township were rated predominantly 1st rate (37.7 percent) and 2nd rate (34.7 percent). Evans did not list the soils rating for 8 miles plus part of another mile. Evans split two section lines, in each case rating the soils 1st rate on the bottomland portions. Of the sections lines that bounded the first parcels sold, most (89.0 percent of the total length) were described by Evans as 1st rate and the remainder (11.0 percent) were 2nd rate. For this descriptive modeling, the "first parcels sold" include those described above as the early land sales in Franklin Township (Union Historical Company 1880, p. 390). "Early farmsteads" include those described above from the Illustrated Historical Atlas of the State of Iowa (Andreas 1875). The distribution of soil ratings for section lines near early farmsteads showed equal numbers for 1st rate and 2nd rate soils (34.6 percent), but more 3rd rate (11.5 percent) than for first parcels sold (0.0 percent).
|Soil ratings||Total (miles)||Percent||First parcels sold (miles)||Percent||Early farmsteads (freq)||Percent|
GLO vegetation types. Deputy Surveyor Evans mapped four vegetation types in Franklin Township. The area Evans mapped as timber covered 7.3 percent of Franklin Township. However, 11.8 percent of the section lines Evans rated 1st rate soils intersected areas that Evans mapped as timber. Therefore, section lines rated as 1st rate soils intersect a disproportionately large percentage of timber. Conversely, section lines rated as 2nd rate and 3rd rate soils intersect disproportionately small percentages of timber (1.2 and 3.3 percent, respectively). Section lines without a soil rating ("not rated") intersect a disproportionately large percentage of timber (13.9 percent), an even higher percentage than 1st rate soils (11.8 percent). The first parcels sold included a relatively small amount of prairie (51.5 percent), but a relatively large amount of timber (32.5 percent) and grove (14.6 percent). Early farmsteads had GLO vegetation characteristics similar to areas with 1st rate soils.
|GLO vegetation types (percent)||Prairie||Timber||Grove||Field||Total|
|All section lines||89.3||7.3||2.5||0.9||100.0|
|First parcels sold (1848)||51.5||32.5||14.6||1.4||100.0|
|Early farmsteads (1875)||84.3||3.8||7.7||3.8||100.0|
Distance to nearest timber/grove, river, field. To measure proximity of each soil rating class to timber, grove, river, and field, distances were measured from each section line midpoint to the nearest timber/grove polygon edge, nearest point along the river, and nearest field polygon edge. The river location used in this analysis is not the current channel, but rather the one shown on Evans' township map. Because both timber and grove could provide shelter, building materials, and fuel, they were aggregated together for this analysis. Midpoints of section lines rated 1st rate are closer to timber/grove polygons (mean distance of 674 meters) than those of 2nd rate soils or 3rd rate soils (1,411 and 1,207 meters, respectively). The same pattern is evident in mean distances to the South Skunk River and seven fields mapped by Evans. These seven fields are even closer to timber/grove (418 meters) than section line midpoints with 1st rate soils (674 meters) or soils not rated (561 meters). The first parcels sold have the shortest mean distance to timber and grove (201 meters) and to fields (545 meters). Early farmsteads had distance characteristics quite similar to areas with 1st rate and 2nd rate soils. Early farmsteads were more distant from GLO timber/grove, river, and field than the first parcels sold.
|Mean distance (meters)||Timber/Grove||River||Field|
|All section line midpoints||971||2,664||1,960|
|First parcels sold (1848)||201||2,249||545|
|Early farmsteads (1875)||1,047||3,474||1,510|
Soil description. Surveyor Evans included description of the soil for ten section lines. Almost all (85.4 percent) of the ten section lines described as "rich" or "sandy" were "not rated."
|Soil description (percent)||Rich||Sandy||Not listed||Total|
|All section lines||10.9||3.7||85.5||100.0|
|First parcels sold (1848)||0.0||0.0||100.0||100.0|
|Early farmsteads (1875)||19.2||7.7||73.1||100.0|
Valley bottom delineation. As instructed by the Surveyor General in the 1846 General Instructions to Deputy Surveyors, Evans included on his township map the edges of the river valley bottom: "On this diagram you are to represent, as you progress with your survey, the crossing and courses of all streams of water and of the bottom land through which they meander." Even though approximately half (51.5 percent) of the 1st rate soils are located in the bottomland area delineated by Evans, only 18.9 percent of the fields are located in the bottomland area. An even smaller amount (7.8 percent) of the 2nd rate soils are located in the bottomland area. None of the 3rd rate soils are in bottomland. In contrast, approximately three-fourths (75.8 percent) of the soils not rated are located in the bottomland area delineated by Evans. The first parcels sold are located predominantly on the upland (83.1 percent) rather than within the valley bottom delineated by Evans (16.9 percent). An even higher proportion of early farmsteads (92.3 percent) were located on the upland.
|Valley bottom delineation (percent)||Bottomland||Upland||Total|
|All section lines||33.1||66.9||100.0|
|First parcels sold (1848)||16.9||83.1||100.0|
|Early farmsteads (1875)||7.7||92.3||100.0|
Land surface. Surveyor Evans included description of the land surface for all but five section lines. Nearly half (44.9 percent) of the 1st rate soil lines were described as "bottom." Only 20.6 percent of the 1st rate soil lines were described as rolling. In contrast, approximately three-fourths of the 2nd rate soils and 3rd rate soils were described as "rolling." None of the seven fields mapped by Evans were described as being in "bottoms." Rather, fields were in areas described as "level," "rolling," and "not listed." The first parcels sold are also in areas described by Evans as "level," "rolling," and "not listed." Though most (53.8 percent) of the early farmsteads were in areas that Evans described as "rolling," a higher proportion than other features were in areas described as "broken" (23.1 percent).
|Land surface (percent)||Bottom||Level||Gentle||Rolling||Broken||Not listed||Total|
|All section lines||23.9||12.7||1.9||45.5||7.6||8.4||100.0|
|First parcels sold (1848)||11.9||30.9||0.0||21.3||14.5||21.4||100.0|
|Early farmsteads (1875)||7.7||11.5||0.0||53.8||23.1||3.8||100.0|
5. Descriptive modeling of modern soil characteristics
Each of the four classes of soil ratings (1st rate, 2nd rate, 3rd rate, and not rated) can be described by examining and measuring relationships with characteristics of soils mapped in the modern soil survey (Dideriksen and Radatz 2000). These soil characteristics include the following:
Landscape position. Soils rated 1st rate by Evans are located predominantly on floodplain positions (51.6 percent) and upland positions (37.8 percent). In contrast, soils rated 3rd rate are located predominantly on swale positions (55.2 percent) and upland positions (44.8 percent). Of the soils not rated, most (70.5 percent) are located on floodplain positions. The seven fields mapped by Evans are located predominantly on upland positions (50.3 percent) and floodplain positions (38.7 percent). The first parcels sold are also located predominantly on upland positions (66.4 percent) and floodplain positions (21.2 percent). Early farmsteads are located predominantly on upland ridge positions (73.1 percent) and upland swale positions (19.2 percent).
|Landscape position (percent)||Floodplain||Terrace||Swale||Upland||Not listed||Total|
|All section lines||32.8||3.8||20.7||41.7||1.0||100.0|
|First parcels sold (1848)||21.2||1.3||10.4||66.4||0.8||100.0|
|Early farmsteads (1875)||7.7||0.0||19.2||73.1||0.0||100.0|
To compare the floodplain landscape position area with the valley bottom delineated by Evans, the Coefficient of Areal Correspondence (CAC) was computed (Minnick 1964, Unwin 1981). The CAC is an index of similarity on a scale of 0 to 1. It measures the similarity in amount and spatial distribution of floodplain and valley bottom. The CAC divides the area of spatial intersection by the area of spatial union. The area of spatial intersection includes the total area of co-occurrence of both floodplain and valley bottom. The area of spatial union includes the total area of either floodplain and valley bottom.
CAC = 2816.6 ha / 3369.0 ha = 0.84
If the area of floodplain along the tributaries of the South Skunk River are excluded, the CAC is higher:
CAC = 2816.6 ha / 3134.2 ha = 0.90
Both CAC measures, particularly the second one (without the floodplain of tributaries), indicate quite high similarity between the floodplain area delineated on the modern soil survey and the valley bottom area delineated by Deputy Surveyor Evans.
A data variable related to landscape position that also indicates topographic patterns is slope. The 10-meter Digital Elevation Model (DEM) available from the US Geological Survey was used to derive a slope steepness grid theme. The soil category with the lowest mean slope is 3rd rate soils (1.6 percent slope). The soil category with the highest mean slope is 2nd rate soils (3.7 percent slope). However, the first parcels sold have a higher mean slope than the 2nd rate soils (6.8 percent slope).
|Mean slope (in percent)||Slope %|
|All section lines||3.2|
|First parcels sold (1848)||6.8|
|Early farmsteads (1875)||4.1|
Drainage class. Approximately half of the township (51.5 percent) has soils of the poorly drained class. The percentage is similar for 1st rate soils, 2nd rate soils, soils not rated, and the seven fields mapped by Surveyor Evans. Almost three-fourths (72.7 percent) of the 3rd rate soils area is poorly drained. This area is on the upland west of the South Skunk River and north of Bondurant. This area contains soils in depressions and swales, such as Okoboji, Harps, Canisteo, Webster, and Nicollet. The lowest percentage of poorly drained soils is for the seven fields mapped by Surveyor Evans (45.9 percent) and the first parcels sold (27.3 percent). The proportions are similar for early farmsteads.
|Drainage class (percent)||Poor||Well||Moderate||Excessive||Not listed||Total|
|All section lines||51.5||10.0||34.6||2.8||1.0||100.0|
|First parcels sold (1848)||27.3||63.6||8.3||0.0||0.8||100.0|
|Early farmsteads (1875)||34.6||57.7||7.7||0.0||0.0||100.0|
Hydric soils. The patterns in hydric soils percentages are similar to those for drainage class. The highest percentage of hydric soils is for 3rd rate soils (55.2 percent). A lower percentage of hydric soils is for 2nd rate soils (38.0 percent). The lowest percentage of hydric soils is for the seven fields mapped by Surveyor Evans (33.7 percent) and the first parcels sold (24.6 percent). This again suggests that the Euro-American settlers who preceded Evans' survey selected field locations that avoided soils with poor drainage. This trend continued to 1875 with early farmsteads.
|Hydric soils (percent)||Hydric||Not hydric||Total|
|All section lines||42.7||57.3||100.0|
|First parcels sold (1848)||24.6||75.4||100.0|
|Early farmsteads (1875)||19.2||80.8||100.0|
Corn Suitability Rating. Corn Suitability Rating (CSR) is a measure of the soil's suitability for modern row-crop agriculture. CSR is expressed as an index from 0 to 100. It was developed at Iowa State University through the Iowa Agriculture and Home Economics Experiment Station and the Department of Agronomy (Fenton and Miller 1996, p. 9).
Corn suitability ratings provide a relative ranking of all soils mapped in the state of Iowa based on their potential to be utilized for intensive row crop production. The CSR is an index that can be used to rate one soil's potential yield against another over a period of time. The CSR considers average weather conditions as well as frequency of use of the soil for row crop production. Ratings range from 100 for soils that have no physical limitations, occur on minimal slopes, and can be continuously row cropped to as low as 5 for soils with severe limitations for row crops. The ratings listed in this table assume a) adequate management, b) natural weather conditions (no irrigation), c) artificial drainage where required, d) that soils lower on the landscape are not affected by frequent floods, and e) no land leveling or terracing. The weighed CSR for a given field can be modified by the occurrence of sandy spots, local deposits, rock and gravel outcroppings, field boundaries, noncrossable drainageways, and so forth. Even though predicted average yields will change with time, the CSRs are expected to remain relatively constant in relation to one another over time.
By the modern standards of CSR, 3rd rate soils have the highest suitability for row crop agriculture (mean CSR = 85.5). This is the same area that contains a high percentage of poorly drained soils and hydric soils (see previous measures above). Soils rated 1st rate and 2nd rate have a lower mean (area-weighted average) CSR (74.5 and 74.4 respectively). The seven fields mapped by Evans have a mean CSR of 82.4, a value closer to 3rd rate soils than 1st rate soils. The first parcels sold have the lowest area-weighted average CSR (65.2). Early farmsteads are on soils with an average CSR of 74.0, similar to 1st rate and 2nd rate soils.
|Mean CSR (area weighted average)||CSR|
|All section lines||74.8|
|First parcels sold (1848)||65.2|
|Early farmsteads (1875)||74.0|
Estimated Corn Yield. Estimated Corn Yield (ECY) is expressed in bushels per acre (Fenton and Miller 1996, p. 9).
The yield estimate for each SMU is based on kind of parent material, slope class, erosion class, natural drainage class, and nature of the subsoil in terms of rooting environment to include limiting layers, soil depth, and plant available water capacity. In addition, potential for periodic flooding and weather conditions are included. Corn yields are estimated for high-level management and are normalized for a 5-year average. High-level management includes the adoption of best available technology for crop production to include agronomic, engineering, and economic practices.
The patterns in measures of Estimated Corn Yield (areas weighted average) are similar to those described above for CSR. The highest yield is for 3rd rate soils (147.6 bu/ac). The lowest yield is for 1st rate soils (130.5 bu/ac). The yield for the seven fields mapped by Evans (146.7 bu/ac) is almost as high as that for 3rd rate soils (147.6 bu/ac). Of all the categories, the first parcels sold have the lowest area-weighted average yield (110.0 bu/ac). Early farmsteads are on soils that have an average yield of 147.0 bu/ac, similar to GLO fields and 3rd rate soils.
|ECY (bushels per acre)||ECY|
|All section lines||131.5|
|First parcels sold (1848)||110.0|
|Early farmsteads (1875)||147.0|
USDA Prime Farmland. The USDA Prime Farmland classification includes six classes (Fenton and Miller 1996, p. 8).
Prime farmland, as defined by the USDA, is the land that is best suited to food, feed, forage, fiber, and oilseed crops. It may be cropland, pasture, woodland, or other land, but is not urban and built-up land or water areas. It either is used for food or fiber or is available for these uses. The soil qualities, growing season, and moisture supply are those needed for a well-managed soil to produce economically a sustained high yield of crops. Prime farmland produces the highest yields with minimal inputs of energy and economic resources, and farming it results in the least damage to the environment. Prime farmland usually has an adequate and dependable supply of moisture from precipitation or irrigation. The temperature and growing season are favorable. The level of acidity or alkalinity is acceptable. Prime farmland has few or no rocks and is permeable to water and air. It is not excessively erodible or saturated with water for long periods and is not frequently flooded during the growing season. The slopes range mainly from 0 to 6 percent. Some soils have a seasonal high water table and soils that are frequently flooded qualify for prime farmland only in areas where these limitations have been overcome by a drainage system or flood control. The need for these measures is indicated by a number following the letter designation for prime farmland. On-site evaluation is needed to determine whether or not these limitations have been overcome by corrective measures.
- P = Prime
- P2 = Prime, where drained
- P3 = Prime, if protected from flooding or does not flood more than once in 2 years during a growing season
- P5 = Prime, where drained and protected from flooding
- S = Statewide Importance. These are soils that generally also can be highly productive for cropland, but occur on slopes greater than 6% or have limitations in drainage or flood control that are more difficult to overcome. These soils are in capability class 3 or 4. At this time, the soils identified as statewide importance are a potential listing as it has not yet been approved by the State of Iowa.
- L = Local Importance. These are soils that generally are poorly suited or unsuited to cropland because of the steepness of slope or flooding and wetness limitations. They may be important in the county, however, for other uses such as pasture, wildlife, or recreation. The soils identified as local importance are a potential listing of soils that may be considered by county officials for this designation.
For this research, the four Prime classes were aggregated. Again, the patterns in percentages of USDA Prime Farmland classes are similar to those described above for CSR and ECY. Third rate soils are 97.2 percent Prime. Only 81.3 percent of 2nd rate soils are Prime. The seven fields mapped by Evans are 92.5 percent Prime (the second highest percentage). The first parcels sold have the lowest proportion of Prime land (65.3 percent) and the highest proportion of land of Local importance (22.8 percent). Early farmsteads have a higher proportion of Prime land (76.9 percent).
|USDA Prime Farmland (percent)||Prime||State||Local||Not listed||Total|
|All section lines||81.7||10.4||6.8||1.0||100.0|
|First parcels sold (1848)||65.3||11.1||22.8||0.8||100.0|
|Early farmsteads (1875)||76.9||11.5||11.5||0.0||100.0|
The total length of section lines with 1st rate, 2nd rate, and 3rd rate soils (51.4 miles) were analyzed in terms of their USDA Prime Farmlands class. (This analysis excludes the section lines for which the soils were not rated by Deputy Surveyor Evans.)
|GLO soil rating||Miles||Percent|
|USDA Prime Farmland||Miles||Percent|
The GLO soil classification has almost equal amounts of 1st rate and 2nd rate soils (44.2 percent and 40.3 percent, respectively). The USDA Prime Farmlands classification is quite different with a predominance of Prime farmland (86.1 percent).
6. Modeling summary
The summary tables below list the common characteristics of each soil rating class (1st rate, 2nd rate, 3rd rate, not rated), along with the most common characteristics of the seven fields mapped by Evans and the township as a whole. For the data characteristics that have numerical values, the numerical values were generalized by using relative terms (such as near, average, and far).
GLO data characteristics. In Franklin Township, 1st rate soils had a lower than average amount of prairie, but a higher than average amount of timber. First rate soils were relatively near to timber, groves, the South Skunk River, and the seven fields mapped by Deputy Surveyor Evans (the nearest of any class). None of the 1st rate soils were described as rich or sandy. Nearly equal amounts of 1st rate soils were included in the bottomland area and upland area delineated by Evans. When describing the land surface, Evans described nearly half of the 1st rate soil area as bottom (the highest percentage of any class).
In Franklin Township, 2nd rate soils had a higher than average amount of prairie, but a lower than average amount of timber (the lowest percentage of any class). Second rate soils were relatively far from timber, groves (the farthest of any class), and the South Skunk River, and close to average distance from the seven fields mapped by Deputy Surveyor Evans. Some of the 2nd rate soils were described as sandy. Most of the 2nd rate soils were included in the upland area delineated by Evans. When describing the land surface, Evans described three-fourths of the 2nd rate soil area as rolling (the highest percentage of any class).
In Franklin Township, 3rd rate soils had a higher than average amount of prairie (the highest percentage of any class), but a lower than average amount of timber. Third rate soils were relatively far from timber, groves, the South Skunk River (the farthest of any class), and the seven fields mapped by Deputy Surveyor Evans (the farthest of any class). None of the 3rd rate soils were described as rich or sandy. All of the 3rd rate soils were included in the upland area delineated by Evans (the highest percentage of any class). When describing the land surface, Evans described three-fourths of the 3rd rate soil area as rolling and one-fourth as level. For five of the seven GLO data characteristics, 3rd rate soils are the same as 2nd rate soils.
In Franklin Township, soils not rated had a lower than average amount of prairie (the lowest percentage of any class), but a higher than average amount of timber (the highest percentage of any class). Soils not rated were relatively near to timber, groves, and the South Skunk River (the nearest of any class), and close to average distance from the seven fields mapped by Deputy Surveyor Evans. Over three-fourths (the highest percentage of any class) of the soils not rated were described as rich; some were described as sandy. Most of the soils not rated were included in the bottomland area delineated by Evans (the highest percentage of any class). When describing the land surface, Evans described nearly half of the soils not rated area as bottom. For four of the seven GLO data characteristics, soils not rated are the same as 1st rate soils.
In Franklin Township, the seven fields mapped by Deputy Surveyor Evans were relatively near to timber and groves (the nearest of any class), but an average distance from the South Skunk River. None of the fields were described as rich or sandy. Six of the seven fields were included in the upland area delineated by Evans. When describing the land surface, Evans described some of the fields as level (the second highest percentage of any class) and some as rolling; however, for nearly half the land surface was not described. For only two of the seven GLO data characteristics, fields are the same as 1st rate soils.
The first parcels sold in Franklin Township are almost entirely surrounded or intersected by 1st rate soils. Compared to the other classes in the descriptive model, the first parcels sold have the lowest percentage of prairie and the highest percentage of timber and grove. Compared to the other classes, the parcels are the nearest to timber/grove and to fields. None of the parcels were described as rich or sandy. The first parcels sold were predominantly outside the valley bottom area delineated by Evans. When describing the land surface, Evans described the area where the first parcels sold are located as level (the highest percentage of any class) and some as rolling (the second lowest of any class). For four of the seven GLO data characteristics, the first parcels sold are the same as fields; this is to be expected, considering their close proximity.
Compared to first parcels sold (1848), early farmsteads (1875) have less timber, are further from timber/grove and river. This may be evidence that by 1875, there was less dependence on timber and river resources. Also, though a large majority (89.0 percent) of first parcels sold were located in areas of 1st rate soils, a minority of early farmsteads (34.6 percent) were located in areas of 1st rate soils. This may indicate that the criteria for agricultural suitability had changed between 1848 and 1875. Another factor may be that less timber land was available for purchase by 1875. In addition, developments in drainage technology may have made farming the upland pothole areas more feasible by 1875.
|GLO data characteristics||GLO vegetation||Distance to timber/grove||Distance to river||Distance to field||Soil description||Valley bottom||Land surface|
|1st rate||Prairie, Timber||Near||Near||Near||Not listed||Bottomland, Upland||Bottom|
|3rd rate||Prairie||Far||Far||Far||Not listed||Upland||Rolling|
|Not rated||Prairie, Timber||Near||Near||Average||Rich||Bottomland||Bottom|
|Fields||Field||Near||Average||--||Not listed||Upland||Level, Rolling|
|First parcels sold (1848)||Prairie, Timber||Very near||Average||Very near||Not listed||Upland||Level, Rolling|
|Early farmsteads (1875)||Prairie||Average||Far||Near||Not listed||Upland||Level, Rolling|
|GLO data characteristics||GLO vegetation||Distance to timber/grove||Distance to river||Distance to field||Soil description||Valley bottom||Land surface|
|1st rate||Prairie, Timber||674||1,694||1,342||Not listed||Bottomland, Upland||Bottom|
|3rd rate||Prairie||1,207||4,715||2,848||Not listed||Upland||Rolling|
|Not rated||Prairie, Timber||561||1,150||2,093||Rich||Bottomland||Bottom|
|Fields||Field||418||2,702||--||Not listed||Upland||Level, Rolling|
|First parcels sold (1848)||Prairie, Timber||201||2,249||545||Not listed||Upland||Level, Rolling|
|Early farmsteads (1875)||Prairie||1,047||3,474||1,510||Not listed||Upland||Level, Rolling|
Modern soil characteristics. In Franklin Township, over half of the 1st rate soils were on floodplain landscape positions and over one-third of the 1st rate soils were on upland landscape positions. According to the DEM, the mean slope of 1st rate soils is slightly higher than the township average. Approximately half of the 1st rate soils are in the poor drainage class and approximately one-third of the 1st rate soils are in the moderate drainage class. Slightly less than half of the 1st rate soils are listed as hydric. For 1st rate soils, the area weighted average CSR and ECY are below the township averages (nearly the lowest for CSR and the lowest of any class for ECY). The percentage of 1st rate soils in the USDA Prime class is slightly above the township percentage.
In Franklin Township, over half of the 2nd rate soils were on upland landscape positions (the highest percentage of any class) and one-fourth of the 2nd rate soils were on swale landscape positions. According to the DEM, the mean slope of 2nd rate soils is higher than the township average (the highest of any class). Approximately half of the 2nd rate soils are in the poor drainage class and over one-third of the 2nd rate soils are in the moderate drainage class (the highest percentage of any class). Over one-third of the 2nd rate soils are listed as hydric. For 2nd rate soils, the area weighted average CSR is below the township average (the lowest percentage of any class) and the ECY is above the township average. The percentage of 2nd rate soils in the USDA Prime class is slightly below the township percentage (the lowest percentage of any class).
In Franklin Township, over half of the 3rd rate soils were on swale landscape positions (the highest percentage of any class) and the remaining areas of 3rd rate soils were on upland landscape positions. No 3rd rate soils were on floodplain or terrace positions. According to the DEM, the mean slope of 3rd rate soils is far below the township average (the lowest of any class). Approximately three-fourths of the 3rd rate soils are in the poor drainage class (the highest percentage of any class) and the remaining one-fourth of the 3rd rate soils are in the moderate drainage class. More than half of the 3rd rate soils are listed as hydric (the highest percentage of any class). For 3rd rate soils, the area weighted average CSR and ECY are far above the township averages (the highest of any class). The percentage of 3rd rate soils in the USDA Prime class is far above the township percentage (the highest percentage of any class).
In Franklin Township, almost three-fourths of the soils not rated were on floodplain landscape positions (the highest percentage of any class). According to the DEM, the mean slope of soils not rated is far lower than the township average. Approximately half of the soils not rated are in the poor drainage class and almost one-third of the soils not rated are in the well-drained class (the highest percentage of any class). Slightly less than half of the soils not rated are listed as hydric. For soils not rated, the area weighted average CSR and ECY are slightly above the township averages. The percentage of soils not rated in the USDA Prime class is slightly above the township percentage.
In the seven fields mapped by Deputy Surveyor Evans, over half the area was on upland landscape positions according to the modern soil characteristics. According to the DEM, the mean slope of the fields is slightly below the township average. Slightly less than half of the field area is in the poor drainage class and the remaining are moderately-drained or well-drained. Approximately one-third of the field area is listed as hydric. For the seven fields, the area weighted average CSR and ECY are above the township averages. The percentage of the fields in the USDA Prime category is far above the township percentage.
The modern soil characteristics show that the first parcels sold in Franklin Township are on predominantly upland landscape positions and have well-drained soils. According to the DEM, the mean slope of the first parcels sold is much higher than the seven fields and the township average. Only one-fourth of the parcels' area is listed as hydric (the lowest percentage of any class). For the first parcels sold, the area-weighted average CSR and ECY are the lowest of any class. The percentage of the first parcels sold in the USDA Prime category is the lowest of any class.
Compared to first parcels sold (1848), early farmsteads (1875) are located on less steep areas with higher productivity as measured by CSR, ECY, and USDA Prime Farmlands designation.
|Modern soil characteristics||Landscape position||Mean slope||Drainage class||Hydric soils||CSR||ECY||USDA Prime Farmlands|
|1st rate||Floodplain, Upland||High||Poor, Moderate||Not hydric||Moderate||Moderate||Prime|
|2nd rate||Upland, Swale||High||Poor, Well||Not hydric||Moderate||Moderate||Prime, State|
|3rd rate||Swale, Upland||Low||Poor||Hydric||High||High||Prime|
|Not rated||Floodplain||Low||Poor, Moderate||Not hydric||Moderate||Moderate||Prime|
|Fields||Upland, Floodplain||Moderate||Poor, Well||Not hydric||High||High||Prime|
|First parcels sold (1848)||Upland, Floodplain||Very high||Well, Poor||Not hydric||Low||Low||Prime, Local|
|Early farmsteads (1875)||Upland||High||Well||Not hydric||Moderate||High||Prime|
|Modern soil characteristics||Landscape position||Mean slope||Drainage class||Hydric soils||CSR||ECY||USDA Prime Farmlands|
|1st rate||Floodplain, Upland||3.5||Poor, Moderate||Not hydric||74.5||130.5||Prime|
|2nd rate||Upland, Swale||3.7||Poor, Well||Not hydric||74.4||134.0||Prime, State|
|3rd rate||Swale, Upland||1.6||Poor||Hydric||85.5||147.6||Prime|
|Not rated||Floodplain||2.0||Poor, Moderate||Not hydric||77.4||132.3||Prime|
|Fields||Upland, Floodplain||2.8||Poor, Well||Not hydric||82.4||146.7||Prime|
|First parcels sold (1848)||Upland, Floodplain||6.8||Well, Poor||Not hydric||65.2||110.0||Prime, Local|
|Early farmsteads (1875)||Upland||4.1||Well||Not hydric||74.0||147.0||Prime|
Evidence for hypotheses. According to the modeling results, areas described as 3rd rate soils are the most productive by modern standards. Soils in these 3rd rate areas are predominantly poorly drained and classified as hydric. They are located in relatively flat upland areas mapped almost entirely as prairie by Evans in September, 1847. Also, 3rd rate soils are the farthest from the South Skunk River and fields and almost the farthest from timber and groves.
In contrast, areas described as 1st rate soils are the least productive by modern standards. These 1st rate areas are predominantly floodplain locations with soils of poor to moderate drainage. Also, these 1st rate areas have almost the highest percentage of timber and are located relatively near timber, grove, river, and fields.
This evidence supports the first hypothesis: the historic GLO classification of soil suitability for agriculture is different than the modern classification of the USDA soil survey. In Franklin Township, the most productive areas were described by Evans as 3rd rate and the least productive areas were described as 1st rate. The poorly drained pothole soils of the 3rd rate area presented an obstacle to pioneer agriculture not removed by technology until a half century later (Peterson and Engelhorn 1946, p. 23). Perhaps the lack of timber and water also made the 3rd rate area unsuitable in Evans' view.
This evidence partially supports the second hypothesis: the GLO soils classification rated areas near river valleys as high suitability for agriculture, especially terrace positions and upland positions, areas near timber resources, and areas with well-drained soils. In Franklin Township, 1st rate soils were relatively close to timber, groves, and the South Skunk River. However, 1st rate soils were located somewhat in upland areas, but primarily in floodplain areas. Also, 1st rate soils were located in areas with a range of drainage characteristics: poorly-, moderately-, and well-drained.
The seven fields mapped by Evans seem quite suitable for agriculture by both GLO standards and modern standards. All were located in 1st rate areas, close to timber and grove. Six of seven fields were in the upland area delineated by Evans. The mean slope within the fields is relatively low to moderate. A relatively small percentage of the field area is listed as hydric soils. The fields ranked relatively high in all three modern measures of agricultural suitability (CSR, ECY, and USDA Prime Farmlands).
7. GLO surveyors' criteria for agricultural suitability
Though the Surveyor General and the Deputy Surveyors do not explicitly define first rate, second rate, and third rate soils, their descriptions of the areas surveyed provide insight into their criteria for agricultural suitability. The following quotations are from field notes written by Deputy Surveyors. Some are descriptions of a particular section line, but most are from the general summative township description written at the end of each township survey. (Unfortunately, Deputy Surveyor Evans did not include a general township description for Franklin Township (T80N R22W) in Polk County.)
Samuel Durham's descriptions associate settlement with "sufficient" timber and water "of a lasting character." He also views the Des Moines River as an attractive transportation route for agricultural produce:
This Township is well supplied with timber and water and is fast filling up with settlers. It will admit of a heavy settlement. Its close contiguity to the Des Moines makes it desirable location to those who look to the Des Moines [River] as a future thoroughfare to convey their produce to market. the North Eastern part of the Township is pretty flat containing a great many reservoirs of water or marshes. Sam'l. W. Durham, September 11, 1847, T79N R23W (Polk County)
This Township is mostly high rolling prairie, generally first rate soil. A portion of the S.W. part of the Township along the breaks of Walnut Creek is broken and covered with oak, hickory and hazle bushes, red root &c. with scattering and inferior oak and hickory timber. Beaver creek is a very large and beautiful creek affording many favorable sites for mills. The prairie contiguous to it is beautiful, and where there is timber sufficient, will invite the attention of the pioneer seeking a location for a farm. Sam'l. W. Durham, October 2, 1847, T79N R25W (Polk County)
This Township is surpassed by few in this District of country in the various qualities admired and sought after by the eager emigrant. It has the high rolling prairie, and the level dry prairie with polished surface, with large and extensive groves of upland and bottom, sufficient to supply a farm on almost every quarter section of prairie in the township The creeks are generally handsome and of a lasting character. The Des Moines is in many places close encompassed with hills and stoney [stony] banks which with the consequent rocky bed afford easy facilities for erecting and propelling machinery. Some stone coal of a good quality is discovered - that mentioned in section 17 has been opened and found to be good, and in great abundance. Sam'l. W. Durham, September 27,1847, 79N R24 (Polk County)
This Township abounds in variety and extend of all properties sought after by the settler. On the North side of the Des Moines are very heavy bodies of first rate white and black oak timber, while the River and creek bottoms are covered with a dense forest of tall and stately timber of every description peculiar to this climate. Keokuk prairie is a beautiful dry, level and generally rich prairie, lying between the Des Moines river and North Three river; it is already in –- a high state of cultivation by the numerous settlers who have been attracted by its beauty and the adjoining easy facilities for making farms and erecting machinery. Agency prairie vies with Keokuk prairie in beauty and fertility-its smooth and polished surface and extraordinary richness of soil, almost surrounded as it is by fine timber, has already drawn the wealthy settler to invest his capital in developing its rich resources. The Coal and sandstone are extensive, and of good quality-the coal mentioned in section 15 is inexhaustible, and fills the whole bluff and bed of the River – Upon the whole it is entirely the best Township in the District surveyed by the undersigned. Sam'l W. Durham, November 19, 1847, T78N R23W (Polk County)
William Henderson and William Neely echoed the need for convenient access to timber and water:
The foregoing Township Straddles Coon [Raccoon] River and Beaver Creek, both of which within this Township has considerable timber, and some verry [very] handsome prarie [prairie] bottoms. There are no Settlers in it, and only two above it on those Streams, It will admit of Many good Settlements, and both Streams are good for Mills and water power, is plenty- The Soil is eaqual [equal] to any in the Country. Wm. H Henderson, November 20, 1849, T81N R28W (Dallas County)
This Township has the East Forth of Des Moines & its timber in its East by afording [affording] mill Sites & advantages for machinery – timber suficient [sufficient] for improving & fencing the fine Sloping prairie West – which is well drained with Brooks of pure water. Wm. J. Neely, November 5, 1849, T88N R26W (Hamilton County)
In addition to water and timber, Johnson Pierson also includes mill sites and rock as important characteristics of suitable areas for agricultural settlement:
This Township is, (the quarter part of it) East of the West Nishnabottana The upland portion of it is not surpassed in beauty and fertility by any in the State. The prairies are well supplied with fine springs of water, and large groves of fine timber are on Walnut Creek from its rapidness in some places I would think might be made very serviceable as a motive agent in propelling machinery, but as yet nothing of the kind has been attempted. The Nishnabottana is a lazy sluggish stream and its waters are muddy eternally from the mud banks which it is furnished with resembling in consistency those of the Missouri River. There is in many parts of this Township abundance of lime rock, which is said to be of a good quality. The land of this region is settling up very fast and it will not be long before it is all (that is the usable part) claimed and in cultivation." Johnson Pierson, June 18, 1852, T69N R41W (Fremont County)
William Neely considered the East Fork of the Des Moines River as having potential for water mills also:
This Township has the East Fork of Des Moines [River] traversing it diagonally – a stream not surpassed by any in the west for beauty & for the advantages it affords at the numerous rapids along it for Mills &c The greater portion of it is timber of an Excellent quality – the adjacent prarie [prairie] Excellent for grain & grass This Township may be classed first rate, three individuals with their families have located here & many claims are being made. Wm. J. Neely, October 22, 1849, T87N R26W (Hamilton County)
On October 18, 1845, GLO Surveyor General George W. Jones wrote about the region containing Franklin Township (T80N R22W):
This portion of the Sac and Fox cession, I am led to believe, greatly surpasses that part included by the recent surveys. The superior quality of its soil, the great abundance of water, the more equal distribution of prairie and timber, an its proximity to the navigation of the Des Moines river, are all sure evidence of the unequalled rapidity with which it will settle (quoted in Lokken 1942, p. 34).
Samuel Jacobs and George Temple also considered bottom lands as productive for agriculture:
I saw important agricultural district conveniently divided into fertile prairie and groves of good timber. Is well watered; well timbered & attracting the attention of settlers. Soil good 2d rate; Surface rolling: The Des Moines river passes through its S.W. corner leaving rich bottom lands on both its banks. Samuel Jacobs, August 21, 1847, T78N R22W (Polk County)
a variety of surface and soil, the bottoms form the luxuriant growth of grass and weeds found on them, cannot be surpassed for richness. Geo. Temple, September 13, 1856, T93N R38W (Buena Vista County)
J.H.D. Street described the type of soil needed for productive agriculture:
Soil generally dry, mixed with sand, fertile, of a kind warm nature, and very productive. J.H.D. Street, December 5, 1851, T72N R41W (Mills County)
The Surveyors did not hesitate to describe areas missing important characteristics for farming. In a few words, A. Leech, William Henderson, and James Davis emphasized the importance of timber to farmers:
Would timber be conveniently procured, it would be most excellent farming land. A. Leech, June 22, 1854, T95N R30W (Kossuth County)
This Township is very destitute of timber, having only a few scattering Trees on Panther Creek, and along its eastern boundary- There is Considerable timber on Coon [Raccoon] River in the Township East of it- There are no settlements or improvements in it, The soil is generally of a productive good quality. William H. Henderson, November 2, 1849, T79N R28W (Dallas County)
The timber is scarse [scarce] & poor & not adapted to building or farming purpose - There are no settlers in the Township. James Davis, November 4, 1847, T79N R26W (Dallas County)
The only Timber on the Township is in the Creek, & that is generally of an inferior quality, mostly Bur oak & Elm- There are no settlers in the Township. James Davis, November 10, 1847, T80N R26W (Dallas County)
According to the Surveyors' descriptions, the prairie potholes characteristic of the Des Moines Lobe landform region were considered a major deterrent to farming potential:
The greater part of this Township is so occupied with ponds and Marshes as to very materialy [materially] affect its value for agricultural purposes. Joseph Moorehead, July 3, 1847, T80N R23W (Polk County)
The prairie where not injured by Marshes and ponds is of a soil that would compare favorably with the richest bottom lands on the Mississippi. Joseph Moorehead, July 16, 1847, T80N R24W (Polk County)
This Township is mostly prairie yet although the soil is of the Richest quality its numerous ponds and Marshes renders it of comparitavely [comparatively] little value. Joseph Moorehead, September 13, 1847, T81N R23W (Polk County)
Is all prairie and so wet and marshy that but a very small part of it is likely to be brought under cultivation at least for many years. Joseph Moorehead, July 24, 1847, T81N R24W (Polk County)
There are many basins and sloughs in the north Eastern part of this Township. They all have drains, go dry in a long dry season, will eventually fill up, may be drained at small expense, will make the best of meadow land, The soil in and about them are generally very rich. William Henderson, October 23, 1849, T79N R27W (Dallas County)
There are many ponds from 6 inches to 4 feet deep contain from ˝ acre to 40 Acres some few larger. generally from 2 to 10 acres. all of which have their drains, or outlets. and it is said, in a long drought most of them go dry, but there will always be a sufficient quantity to supply stock water. William Henderson, August 12, 1851, T80N R29W (Dallas County)
This township has no settlements or improvements, is entirely in an uncultivated condition, is principally poor Prairie, with very many marshes & wet places. James Jackson, November 14, 1849, T87N R24W (Hamilton County)
This township may be said to be a waste of Prairie--hilly or broken and totally unsuitable for agricultural purposes except grazing. Wm. G. Ross, April 23, 1847, T82N R19W (Marshall County)
This Township is mostly prairie of a very good 2nd rate- Soil well adapted to grain & grass. No improvements The East Fork of Des Moines river runs through the W. Side of it affording at its many rapids sites for mills &c In short this Township is 2nd rate for Land-timber & advantages for farming. Wm. J Neely, October 29, 1849, T88N R25W (Hamilton County)
Upland soil is mostly poor, being either gravel or else cold, wet, and sterile. Horatio Waldo, August 22, 1851, T83N R29W (Greene County)
Wet bottom lands were also considered "unfit for cultivation:"
Surface level and marshy; whole line a very fine frog pond, unfit for cultivation; Soil mud. Musquitoes very thick and large ~ soil produces little else. Johnson Pierson, June 18, 1852, T69N R41W (Fremont County)
However, William Henderson envisioned agricultural use of wet areas, especially if they were drained:
This Township Straddles Coon [Raccoon] River, on both Sides of which, there is considerable timber, And there are about 10 families residing in it, most of them have tolerable farms- and are able to buy There are Several rich prarie [prairie] bottoms the Eastern half will soon be settled The Western is not so convenient to timber, the Soil is generally good, There are Many basins and Sloughs which can be drained, the Soil in and about them is good and well calculated for meadows. Wm.H. Henderson, November 10, 1849, T80N R28W (Dallas County)
This Township is destitute of timber except on its western boundary. There can be a heavy settlement made along this boundary, as the timber is somewhat extensive. There are now 8 families, residing in and near this timber, and are busily engaged in improving The Soil in this Township is well calculated for farming & grazing there are many basins and sloughs which go dry in a long dry season, they may all be drained, the soil in and about them is generally rich & will make good meadows. Wm. H. Henderson, December 4, 1849, T80N R27W (Dallas County)
There are a great many sloughs and basins throughout this Township Most of which becomes dry in along dry Season, they will in time fill up. may be drained at small expense, and would then be good land, the Soil in and about them being of a rich quality, and well calculated for Meadows. William H. Henderson, November 2, 1849, T79N R28W (Dallas County)
In summary, GLO Deputy Surveyors emphasized in their field notes positive characteristics of "important agricultural districts:"
Other positive characteristics mentioned by the Surveyors included the following:
GLO Deputy Surveyors also identified negative characteristics of the landscape in terms of its potential for agricultural use:
These characteristics support the modeling results for Franklin Township. First rate soils are on bottoms, near timber and water, but not near poorly-drained swamp land, steep land, or inferior timber.
8. Settlers' criteria for agricultural suitability
Based on a review of literature, Euro-American settlers in Iowa held a variety of opinions and used a variety of strategies when selecting land for farming purposes. In the May 17, 1838, issue of the Iowa News (Dubuque), an article commented on the difficulties of farming in the thick prairie sod:
The plowing of the prairie is a laborious and expensive process, requiring 3 or 4 yoke of oxen, but the timber land is easily plowed after it is cleared.
In 1839, settler Louis Pelzer described another strategy for farming in the thick prairie sod:
On the prairies [near Iowa City] the thud of the axe could be heard as the farmer chopped holes in the sod to receive the seed.
For these reasons, some settlers preferred farming the timbered land:
My object was to find prairie, timber, and water power in conjunction, within a moderate distance of good markets. When I first came, it was impossible to get timber and prairie adjoining without paying a high price for the claim on it. For as much as I have ploughed among stumps, I still prefer timbered land before prairie. Cyrus Sanders, June 22, 1839 (quoted in Swierenga 1968, p. 82).
However, some settlers (even Cyrus' brother) disagreed:
Stake out smooth, level prairie of the richest kind of soil, with not a tree or bush on it. Richard Sanders, Highland, Ohio.
At the time, there was considerable disagreement whether the prairies or timbered lands made better farmland. Traditional farmers believed that stands of timber indicated fertility of the soil while prairie soil was assumed to be barren (Sage 1974).
We are often told by eastern scientific empirics of the sterility of the soil where the prairies are, but the reverse is the fact. Caleb Atwater, 1829 (quoted in Swierenga 1968, p. 85).
Historian Allan Bogue (1963, p. 39) described the relative value of prairie land and timber land, at least to the earlier settlers:
In one respect claim-club activity was linked to the peculiarities of the prairie environment. Had the lands of the Middle West all been equally attractive to settlers, there would have been less reason for clubs; almost invariably land remained unsold after the federal auction. But, to the settler, timbered land was much more valuable than plain prairie, and of timber there was not enough for everyone. Claim-club activity, therefore, was often an effort to corner the wooded land of a new community.
In 1849, William Williams described his land buying strategy (quoted in Swierenga 1968, p. 83):
The only plan is to select good Prairie Land, well watered & buy 20 or 40 acres of Wood Land to Supply it. any quantity can be bought at $5 p Acre. The Wood Land is generally on the bluffs. The Prairie Land is far preferable for farming purposes.
Writing in 1812, Amos Stoddard agreed:
The [prairie] soil is of a luxuriant nature, and yields in abundance; but the want of wood and spring water, of which this prairie is almost destitute, obliges settlers to plant themselves on the margin of the high grounds.
Some land buyers were not deterred by wet land and seemed to have a sense of humor about it. In 1855, land speculator Andrew Jackson Sterrett wrote about the rush for government land in Webster County, near Fort Dodge (Swierenga 1968, p. 92):
No matter what the quality of value, people only seem intent upon getting the number of acres or quantity of Surface, be it land or water. I know a great many people who are prepared to go to raising geese and ducks in this country--having ponds & pasture too in great abundance for that business.
Earle Ross (1951, p. 9) described drainage and other obstacles to Iowa's early farmers, especially on the poorly drained Des Moines Lobe:
Much of the land was wet and swampy, necessitating drainage to make it cultivable or highly productive. The same region contains occasional evaporated lake beds and areas of peat soil which have involved special problems of modification and adaptation.
Settlers and historians also describe timber as an important element of settler farming operations. Swierenga (1968, p. 18, 20) described the counties in central and south central Iowa that were part of Royce Cession No. 262:
A gentle and rolling topography with good natural drainage, sufficient vegetation, and excellent soil quality were the major physical features that interested land buyers. Almost every township in the cession claimed timber suitable for fuel, fencing, and often for building materials.
Bogue (1963, p. 42) said that wherever the GLO surveyors "drove their stakes or built their mounds, the land-speculator or his agent was sure to follow. Indeed, on occasion, he was even ahead of the surveyors." Swierenga (1968) reported that Samuel J. Bayard, Receiver at the Fairfield Land Office, was a land speculator who tried to buy land with "a gentle and rolling topography with good natural drainage, sufficient vegetation, and excellent soil quality." The first land claimed offered a combination of natural water supply and some timber along with prairie. Schroeder (1983) described a similar situation in Missouri:
A cabin location on the edge of the timber, accessible to the springs in the valley as well as the native grass of the uplands for livestock, was the preferred site. The bottom grasses were used from the start for wintering animals.
In his study of the ten largest land speculators in the Royce Cession, Swierenga (1968) classified the soils of 7,617 40-acre tracts.
The choicest locations were those that contained a judicious combination of prairie and wood (a ratio of three acres of prairie to one of timber was considered ideal), and, of course, water. This usually meant a farmstead at the edge of the woods, with the home built in the shelter of the timber and the fields laid out on the adjoining prairie (p. 82).
Potholes apparently were a matter of no greater concern than flat or rolling topography (p. 93). Speculators preferred prairie in combination with timbered land over prairie without timber, when both were available (p. 90).
Soil type and topography were apparently more important than proximity to the county seat, major towns, or important rivers. The large buyers [speculators] seemed to prefer prairie land near lesser water courses (p. 94).
The largest speculators purchased more woodland and less prairie than the other entrants in the first year of sales, but in the remaining years they acquired as much or more prairie than the rest (p. 92).
Swierenga (1968, p. 81, 98) concluded that much of his evidence contradicts the general belief that land buyers before 1850 preferred timber land along streams and that land buyers after 1850 preferred prairie tracts on uplands. Speculators would first choose land with a combination of prairie, timber, and water. If that type of land had already been claimed, speculators would second choose dry, smooth, fertile prairie soil. Of lower importance to speculators were proximity to towns and mills and directional patterns of settlement. Therefore, criteria changed as settlement progressed and the type of land available changed.
Bogue (1963, p. 6) described the significance of soil type on the selection of farming locations by settlers:
In the woods along the prairie watercourses, the pioneers were to find soils of lighter color, for organic matter accumulated less rapidly in soils under forest cover than under grass. There was less sustenance for the crops of the farmer in these soils than in those of the true prairie. The modern agronomist distinguishes dozens of different soils in Illinois and Iowa that vary from each other in profile, color, texture, and mineral components; on occasion he groups them in a smaller but still considerable number of soil associations. The soil scientist, however, was not on hand to advise the pioneer.
In a report on his travels in the Midwest, Gottfried Duden (1829, p. 247) described agricultural suitability in the Mississippi River valley:
Fertility decreases with the distance from the Mississippi. The greatest expanses of fertile topsoil are near the biggest rivers. What areas could be better situated for communication with the world than the banks of the Mississippi?
Based on his travels along the Missouri River, Duden (1829, p. 55) provided this description of agricultural suitability of the area:
I must emphasize strongly that the meaning of the words fertile soil in these regions is very different from that in Germany. Good soil, or first rate soil, does not require fertilization during the first century, and during the first decades is too rich even for wheat. This is true of river valleys, especially those of the Missouri. Average, or second rate soil, is of the kind that during the first twelve to twenty years fertilizer cannot increase the yield of the harvest. Because the hills adjoining the great rivers belong in this class the duration of natural fertilizer depends very much on the degree of the incline and the erosion caused by heavy rains. The poorest soil is found in the forests closer to the prairies. The prairies themselves, however, are again, for the most part, as fertile as the hills next to the river valleys.
This is the only definition of first rate, second rate, and third rate soils found to date by the researcher. Unfortunately, no definitions were found in the Surveyor Generals' instructions to Deputy Surveyors or in their field notes. However, writers of the time used language similar to Duden's, but with more general explanation. One example is by Scottish preacher, philosopher, and scientist Thomas Chalmers (1832), who wrote "On the Increase and Limit of Food:"
After all the first-rate land had been cultivated, an increasing population flowed over, as it were, on the second-rate land; which, in virtue of its inferior quality, yielded a scantier return for the same labour. As mankind continued to multiply, a still farther descent behoved to be made, through a gradation of soils, each of less fertility than the one before entered on; and so, either requiring a greater amount of labour to draw from it the same food, or yielding a smaller amount of food to the same labour. This process, it is evident, admits of being extended, till the produce of the soil last entered on shall, by the utmost labour which men will expend on it, be barely sufficient for the subsistence of its agricultural labourers, and of their secondaries.
At the outset of the world -- men reposed in the lap of abundance; and, with no other fatigue than that of a slight and superficial operation on a soil of first-rate quality, richly partook in the bounties of nature. But when all this soil came to be occupied, and the race continued to multiply, land of a second quality behoved to be taken in -- and the conception is, that, at every such transition from a better to a worse land, a heavier imposition of toil was laid upon workmen, and a smaller amount of produce was yielded to them in return for their industry.
With the scraping and stirring of first-rate land by the branch of a tree, there might be as much of real muscular work required to obtain from it the same quantity of produce, as from second-rate land by means of a wooden spade, or from third-rate land by means of an iron one, or from fourth-rate land by means of a plough, or lastly, from fifth-rate and following lands, by means of those successive improvements in the form of the plough, whereby it is made more effective than before.
This accounts for the population being stationary in many countries, where, as yet, the first-rate soils have scarcely been entered upon -- and it should convince us, that something else than the mere energy of this principle must be adverted to, when we reason on that historical progress which has conjunctly taken place, in the extension of husbandry and in the numbers of mankind.
Travel writer Flint (1832, p. 318) described the soils of Illinois as part of "the face of the country:"
The high and rolling prairies are sometimes chequered with groves of sparse trees. The quality of their soil seldom exceeds second rate, and they abound with springs.
To settlers, an important enticement of buying farmland was the freedom to choose the type of land and its location according to their own preferences (quoted in Swierenga 1968, p. 82):
It is most enticing to settle in a region, where one can be absolutely free in one's choice to select one's land, wholly according to one's taste, in the forest or on the prairie. Gottfried Duden, 1829.
You find everywhere some who prefer prairie to woodland, and others who prefer woodland to prairie; the latter generally coming from hard-wood portions in other States. Charles Lindsey, 1860.
Ross (1951, p. 13-14) reemphasized cultural and geographical origins of settlers as important factors in the initial selection of agricultural land:
As in all other western settlement before the extension of through-line transportation, the migration was mainly a secondary one from the Old Northwest and Old Southwest. Ohio, southern Indiana and Illinois, Kentucky, Virginia, North Carolina, and Pennsylvania were represented with especial prominence. As always with pioneers, their conscious choice of a farm home was influenced and limited by their previous experiences. The settlement of Iowa provides one of the many refutations of the Ricardian assumption of the utilization of land in the order of its grades of productivity. Future production possibilities, where understood, had to be subordinated to the immediate demands of subsistence and of pressing obligations. At a time when the basic principles of soil science were just being formulated, the pioneer settler could not be expected to give reasoned consideration to structure, drainage, and erosion problems. The potential fertility of his "folly slough" in no way compensated the youthful Vandemark for the immediate loss of his "plough land" [apparently a reference to Vandemark's Folly by Herbert Quick].
In common with all individualistic pioneers, those of the Iowa country were fearful of the strange and untried. Hence, the first comers in Iowa, as in other portions of the prairie plains, kept to the timbered areas along the streams and ventured out on the open prairies only in a supplemental and tentative way, while the home base remained in the familiar and dependable forest surroundings. Timber was cleared off laboriously in preference to breaking the virgin sod. The clearing dweller, combining limited cultivation and stock grazing with hunting and trapping, was in great contrast to the later prairie farmer.
Ross (1951, p. 32, 43) then described how the agricultural expectations of the "later prairie farmer" had changed by the 1850s.
The settler of the fifties came not to just subsist--to hunt and trap and fish and clear a vegetable patch on his precarious claim--but to farm. The contrast between the estimated "cost of opening a farm in Iowa" and the meager necessities of the pioneer of a decade before measures the changed conditions. The expenditures for machinery and livestock constituted the main increments of additional expense. Both were characteristic of the "agricultural transformation" that was fully under way. The prairies were admirably adapted to the use of machinery. Soil and climate, as well as the experiences of earlier frontiers, encouraged a diversified cultivation, rather than a one-crop system.
By the fifties, both of these events [coming of railroads and reaping machines] had come to determine increasingly the production and marketing of farm products in the strategically situated areas.
Bogue (1963, p. 8, 12) described a similar delay in settlement of Illinois prairie counties:
Pioneer farmers reached the interior prairies of northcentral and northeastern Illinois last among all the regions of the state. Lacking adequate water transportation and presenting many problems of adaptation to the farmer, these prairie counties waited for their full quota of settlers until the 1850's and thereafter.
In reality a very complex combination of factors controlled the flow of settlement into any particular locality. Transportation routes and facilities, potential markets, the quality of the land, real or imagined, location in relation to older settlements, and the state of the settling-in process there--all had important effects upon the development of new areas.
Bogue (1963, p. 13) also described plentiful supply of land in relation to the demand, especially in the early years of settlement:
Occasionally, settlers did congregate along the boundary line of a new purchase in Iowa, waiting for the opening. This behavior was not so much evidence that the lands in older areas were completely occupied as it was of the speculative bent of the "sooners," who coveted the best waterpower and town sites, and the choicer timberlands of the new region.
Although in some regions, settlers did precede the federal surveyors, these forelopers could organize claim clubs to protect their holdings, and the federal surveyors were seldom long in arriving. The large amounts of land purchased at private entry subsequent to the public auctions at all the prairie-land offices in Iowa and Illinois suggest that the settlers did not press hard upon the available supplies of land in the early years of settlement.
All of the settler and speculator land buying criteria examined in this research indicate diversity rather than singular agreement. Criteria were influenced by previous farming experiences, cultural background, type of land available for purchase, timing, transportation, technology, and strategies for dealing with needs (such as wood and water) and obstacles (such as potholes and other wetlands).
9. Conclusions and recommendations
In general, the research results from Franklin Township (T80N R22W) in Polk County, Iowa, support the two research hypotheses.
The research evidence supports the first hypothesis: the historic GLO classification of soil suitability for agriculture is different than the modern classification of the USDA soil survey. In Franklin Township, the most productive areas were described by Evans as 3rd rate and the least productive areas were described as 1st rate. The poorly drained pothole soils of the 3rd rate area presented an obstacle to pioneer agriculture not removed by drainage technology until a half century later. Perhaps the lack of timber and water also made the 3rd rate area unsuitable in Evans' view.
The research evidence partially supports the second hypothesis: the GLO soils classification rated areas near river valleys as high suitability for agriculture, especially terrace positions and upland positions, areas near timber resources, and areas with well-drained soils. In Franklin Township, 1st rate soils were relatively close to timber, groves, and the South Skunk River. However, 1st rate soils were located somewhat in upland areas, but primarily in floodplain areas. Also, 1st rate soils were located in areas with a range of drainage characteristics: poorly-, moderately-, and well-drained.
The seven fields mapped by Evans were established by "preemptors" (squatters) before the GLO survey and before government land sales started in Franklin Township. Though the seven fields may be considered "choice" locations for agriculture in the township, the first parcels purchased by settlers may also be considered "choice" locations. The first 14 parcels sold to 5 buyers by the GLO land office (on October 30, 1848) have characteristics quite similar to the seven fields, with two exceptions: (1) the first parcels sold have a much higher mean slope than the fields and (2) the first parcels sold have a much lower mean CSR and mean ECY than the fields.
The greatest limitation of these GIS modeling results is that they apply to only one township in Iowa. Though the insight provided by a variety of GLO Deputy Surveyors' field notes also agrees with the results of the GIS modeling and supports the research hypotheses, more research is needed to broaden the geographic scope and the depth of the related literature. The following recommendations help to provide more research evidence that specifically addresses the hypotheses:
10. Literature cited
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Last update: 18 November 2004