- Description
- Survey Map
The Land Ordinance Act of 1785 required that land sold by the United States government must be surveyed and subdivided using Public Land Survey System (hereafter PLS). Work began in 1848, 10 years prior to Minnesota statehood, and was finished in 1907. Surveyors started in the south and worked northward.
The PLS is much more than just a systematic division of land. Plat maps, as they are known, are scaled hand drawn maps that show the division of land but surveyors were also contracted to record lakes, rivers, swamps, waterfalls, and areas of prairie and forest. They even include bank meanders in areas with navigable watercourses or sizeable lakes, and man-made features like settlements, roads, trails, and plowed fields are noted in some cases. The surveyor’s field notes, which are not included on the plat map, have more detailed information like types of soil and vegetation and mineral deposits. The PLS is arguably the best dataset in use to determine what Minnesota’s plant communities looked like prior to European settlement, and most of the pre-settlement data discussed here is based on work done on the Survey. It should be noted that the PLS was not a vegetation sampling method but rather a survey method to identify what existed on the land to determine overall value.
We wanted to get a closer look at the plat maps for the townships where SMSC owns property. Most of SMSC property is on Eagle Creek Township which is now completely annexed by the cities of Prior Lake, Shakopee, and Savage. The southern-most SMSC parcels are in Spring Lake Township. Plat maps have been captured in a high resolution digital format and are available for download. We downloaded Spring Lake and Eagle Creek Townships and geo-referenced the plat images to township-range-section spatial data using a GIS. We used other GIS tools to digitize map features originally surveyed on the plat map and to calculate acreage. The analysis yielded some interesting results, and we now have a good idea of what Eagle Creek and Spring Lake Townships were like in 1854 and 1855 when the surveys took place.
According to the GIS analysis, nearly the whole northern half of Eagle Creek Township was classified as ‘prairie’ and ‘oak openings’ by the land surveyors. Bearing tree data and vegetation descriptions along section corners and midpoints corroborate that oak species, particularily bur oak (Quercus macrocarpa), dominated. Surveyors classified these areas as oak openings, and it is likely that the bur oaks were spread out open-grown trees with prairie grasses and forbs in the understory, which is today known as oak savanna. It is difficult to determine how much actual acreage of prairie and oak savanna there was in this portion of Eagle Creek Township but we calculated roughly 8,200 acres of prairie and 1,800 acres of oak savanna according to the analysis.
Forests dominated the rest of Eagle Creek and covered all of Spring Lake Township. These forests were probably ‘Big Woods’ characterized today as sugar maple/basswood forest or oak forest. The surveyors didn not differentiate between forest types but they did record species from bearing trees and vegetation types in field notes during their surveys which can give clues to the overall species composition of pre-settlement forests. We calculated 29,350 acres of big woods forest in the analysis for the two townships (see [Survey Map] tab).
We digitized other features like trails, roads, farmfields, homesteads, wetlands, and open water environments, classified by surveyors as ‘marshes’, ‘sloughs’, ‘swamps’, ‘ponds’, and ‘lakes’. We counted only 10 homesteads and 16 farmfields totaling about 350 acres in the entire two townships (see [Survey Map] tab).
Settlers started accessing this area en masse around this time from major city ports off the Minnesota River. Roads were likely relatively new but major travel thoroughfares and trails were probably long established by Native Americans or game. It appears modern County Roads 83, 16, and 17 seem to be built on old pathways, and they provided a means to access otherwise difficult to get to areas. Perhaps these early roads and others were the beginning-of-the-end for unfragmented large-scale natural systems. Eagle Creek and Spring Lake Townships were still a very natural area in 1854 and 1855 but conversion had begun.
