The Columbia River at
The Dalles, Oregon

The Columbia River at The Dalles, hand-drawn watercolor image of microorganisms in a circle with a charcoal background

Columbia River at The Dalles, Oregon, 2021 — Ink, watercolor, algae pigment, and forest fire charcoal on paper

My second piece is based on a similar sample as the Columbia River at the Deschutes River. The Ehrenberg collection lists the Columbia River in two samples labeled similarly:

. . . among Confervae [filamentous algae] found on a Unis from Colombia River Oregon.

As is the case with all the Columbia River samples, I believe these were originally collected during the Frémont Expeditions of 1843–44, or the United States Exploring Expedition, preserved as dry specimen cards, and given to Dr. Ehrenberg in 1845 after the first expeditions concluded.

Map detail of The Dalles area from the 1843–44 Frémont Expedition, note that Portland is not yet a mapped location at this time. Image sourced from the Library of Congress.

Map detail of The Dalles area from the 1843–44 Frémont Expedition, note that Portland is not yet a mapped location at this time. Image sourced from the Library of Congress.

Based on the colonial settlements at the time where the expedition would potentially pause, The Dalles is a very likely collection site. The Dalles has always been populated by the many First Nations people of the area, and by the early 1800s was a well-established fur trading area. At the time of the sampling, The Dalles was home to the Wascopam Mission. Later, The Dalles would become a critical stop on the Oregon Trail.

Today, The Dalles is a small community surrounded by agricultural areas, following the pattern of intense agricultural intervention found in many of the Columbia River adjacent communities. The Dalles Dam is also located in this area, one in the network of hydroelectric plants common on the Columbia River and its tributaries.

This sample seems more true to the original source as it was collected among filamentous green algae bloom on the Columbia River in The Dalles, OR.

Wascopam Mission, circa 1838

Wascopam Mission, circa 1838

Columbia River collected at Riverfront Park in The Dalles, OR in July 2021.

Dr. Ehrenberg’s observations

Columbia River, Oregon organisms observed by Dr. Ehrenberg. Image used with permission from the Natural History Museum of Berlin.

Dr. Ehrenberg’s illustrations have several species such as Cymbella (shown as a fragment in the illustration), Encyonema, Cocconeis, Ameoba, Gomphonema and many other diatoms. This illustration likely used multiple reference samples and represents a combined microbiome.

My observations

Unlike the Columbia River sample collected at The Deschutes River, this sample differed from the reference image Dr. Ehrenberg illustrated. Although I found common organisms such as Cymbella and Gomphonema, I also found several types of Desmid and most excitingly, the mind-bending fractals of Hydrodictyon. Hydrodictyon was a major inspiration for my composition.

I’m not surprised that this sample was a lot different from the historical sample. With intense agriculture, a major hydroelectric plant, and a highway nearby, this sample reflects a very changed landscape.

Algae bloom on the Columbia River near The Dalles dam

Algae bloom witnessed on the shore of the Columbia River, The Dalles, OR