Reconstructing the Willamette Valley Camas Swales

In recent work I have begun to document the various wetlands of the Willamette Valley from before settler changes took effect. Our best, and most complete set of records of this early period are the General Land Office (GLO) Maps housed now online at the Bureau of Land Management’s Land Status and Cadastral Survey Records website. The earliest surveys were in 1851 up near the Columbia and most begin in 1855 or 1856 in most areas of Oregon. The maps are a series of quadrangle maps that are coded east or west depending on where the land lies in reference to the Willamette Meridian, a central line that bisects the valley. The Willamette Stone, in the Tualatin Hills sets the start of the line. Today the Willamette Meridian is not used in maps but we have to know about this early surveying to understand how to get the data from the survey maps.

The cadastral survey maps cover the whole of Oregon. Many of the early maps are incomplete as surveys were only initiated to address settler land claims and many of the areas left incomplete were mountainous and intractable areas where no one wanted to settle. Surveys would be contracted and when areas were quickly settled the surveyors would be hired to measure the land using a set of chains. They would have a lot of problems with swamps and marshes and lakes as well as hills and mountains. There are also maps of the same areas several years apart, or when many land claims change hands or were altered and subdivided. Some surveys were taken for the reservations and many of these surveys do not appear in the regular GLO series but are instead at the BIA cartographic records, likely at College Park, MD. Some survey records for reservations were noted at NARA Seattle when last I visited in 2010 and I am anxious to go back there to get copies.

But this project was initiated to attempt to document the significant wetlands in the valley, some of which are labelled Camas Prairie or Camas Swale. Camas prairies were likely the dominant landscape for large areas of the valley, especially those areas which flooded after seasonal rains. The camas is just the most easily identifiable plant species for much of the prairie because of its prominent blue to purple flowers which erupt each year (April to June) in large prairies. Other plants are lower growing, not so prominent, and therefore were not known by American surveyors as much. The individual surveyors must have had different skill-sets and knowledge of plants, environments, and landforms so probably not all camas prairies are documented equally. As well, if the survey happened outside of the April to June camas eruption in the valley, the surveyors would not see the camas at all. The documentation then would probably state wetland, marsh, swamp, or swale  or prairie (mid to late summer) as is labelled on numerous maps. Lakes and rivers too would overflow after summer freshets (a soaking storm of rain which causes flooding.)

By studying camas prairies today we know what sorts of environments will host camas and other root plants  and therefore I suspect that any or all of the wetland environments could have a good growth of camas or other root plants. There were a significant number of these wetland environments documented in the 1850s on the GLO maps.

The first example is from the western Tualatin Plains, west of Forest Grove


Overlay of swamps noted in plats 2s, 4w (top), and 3s, 4w, West side of Tualatin Valley


Lower section of plat 2s, 4w overlaid above, note the word “Swamp” inside the wetland marks


Similarly, at Wapato Lake here is great detail of the extent of the lake system, the traditional lake does not end, but proceeds about the same distance south as a marshy swamp into the foothills. Presumably the lake was full of wapato, and wapato is a wetland plant, but as noted in my previous essay about Lake Labish, wapato can grow without being covered by water, and is perhaps less productive but still could be covered in water during seasonal rains as suggests in newspaper accounts. As well the more swampy area could have easily hosted camas and reed plants which would also be subject to harvest. The swampy area is in part the area which drains the foothills of water so the water would flow into the lake through the swamp.

side by side images of wapato Lake (GLO map on right) noting the marshy swale or swamp which extended far south of the central lake, near Gaston Oregon. Wapato Lake GLO  map is a composite of Plats 1s, 4w, & 2s, 4w, & 2s, 3w.

French Prairie and Lake Labish north of Salem have many details which pop out when looking at the GLOs for this area. The overall number of wetlands is very numerous suggesting that there was plenty of water, seasonal swales, and marshes in this area and therefore lots of root plants for harvest by the Kalapuyans,as well as plenty of wildlife for hunting.

The “Mirey Swamp” on French Prairie had to have been a major resource area, then also Lake Labish, and the large wetland and “Poison Lake” by Mt. Angel would too be important areas for food plants, from a composite of GLO maps in this area.


Poison Lake and wetland at 6s 1w


“Mirey Swamp or Slough” at French Prairie 5s, 2w


Lake Labish and its swampy wetland at 6s, 2w, the wetlands extend on both sides of the lake for at least another mile.


Then west of Salem, between Rickreall, Eola and Basket Slough is a noted Camas prairie on the GLO map.

“Wet Camass Prairie” west of Eola


Wet Camass Prairie on GLO map 7s, 4w

The other camas prairie noted in the GLO maps is one approximately 7 miles north of Creswell and about 3.5 miles south of Goshen and the Highway 58 junction with I-5. It is also adjacent to the Coast Fork of the Willamette. This Camas Swale is noted today with an I-5 roadsign as well.

“Camas Swail”- noted with this spelling on another map


“Camas Swale” GLO map 19s, 3w

There is much more to be added to my map of the eligible wetlands for camas and other root crops. But this short study suggests that the original environment of the whole valley was much wetter than today, water remained in the valley longer and the native plants adapted to this environment over thousands of years. This begins the reconstruction of the Kalapuya environments, a necessary study to be able to understand how they lived and where they got their foods. The wetland are examples of highly productive prairies which would be accessed by the Kalapuyan peoples for hundreds if not thousands of years. Adding these highly productive environments to descriptions of the individual tribes will help with description of how far they would travel to get foods. These highly productive wetland prairies would also host lots of wildlife and attract deer and elk. The amount of wetlands in the valley suggests that the area may have been nearly as productive as ocean shorelines which are the most productive habitats on earth and where the largest human populations live. We may need to adjust anthropological carrying capacity estimates for the Kalapuyan environments because of this. These are also likely the best environments which would yield the best results for those wishing to restore native food systems in the valley.  If anyone wishes to join me shoot me an email and we can construct the map together.

Update: numerous responses suggest a volunteer effort to document these environments is possible. I will work to open up a crowdsourced map project for the volunteers. thanks


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