Mapping Lake Lahontan—with contour lines & color

Landscapes past and present emerge from a surveyor's lines, as if by magic.

In 1881, Israel Cook Russell set out to map a lake that had been gone for 10,000 years, one that had filled the dry basins of northwest Nevada with fresh water. He was eager to survey the great lake, to study its features and learn about its life from beginning to end. And the timing was good! In line with practices of the day, the lake’s story would be told in maps that were artistic as well as utilitarian. 

Russell and several assistants spent three field seasons criss-crossing the immense basin of Lake Lahontan (1). They traversed “broad silent plains of desolation” and rugged mountains “unclothed by vegetation”, often in brutal conditions—hot, dry, no shade to be had. Yet they spared no effort. They surveyed basins past and present, sketching and describing sediments, gravel bars and relic shorelines. All was done in meticulous detail and with great precision (DRHMC).

Rarely did vegetation interfere with line of sight in surveys (ancient Lake Lahontan, now Carson Desert).

"section of Lahontan sediments”; note detail, precision typical of late 19th century scientific illustrations.

Fieldwork ended in the fall of 1883, with a visit by Russell to the far west part of the Lahontan Basin. Just two years later, Geological History of Lake Lahontan: a Quaternary lake of northwestern Nevada (Monograph XI) was issued by the US Government Printing Office (2).

At that time, distribution of GPO publications was governed by law (source). Members of Congress each received a set number, for constituents and institutions in their district. A separate run was ordered by the source of the document, in this case the USGS, to share with colleagues, scientists, other programs and institutions, and international exchange partners.

Surplus copies often were available for purchase, probably at cost-recovery prices (3). I bought a first-edition copy of Monograph XI, issued in 1885, from a rare book dealer for $40—not exactly a cost-recovery price, but reasonable (4). 

When Monograph XI arrived, I was truly astonished! It measures 9 × 12 inches, weighs 3 pounds 14 ounces, and includes 302 pages of front matter and text with 35 figures, all printed on smooth high-quality wove paper. Forty-five plates on heavier stock, each protected by interleaving tissue, are spread through the book, including 19 maps.

Plate XXXVII: Imitative Tufa forms.

Plate XLVI (excerpt) showing mountains, basins, playas, and an ancient lake.

While Russell and his crew measured, mapped, noted and sketched, chief geographer Henry Gannett was setting up the Survey’s Topographic Branch, including standards and practices for mapping. There were choices to be made, for example between easy-to-interpret hachures and information-rich contour lines.

In the late 1800s cartographers were still debating how to show topography, the shape of the Earth’s surface. What was the best way to create three dimensions on a flat sheet of paper? Europeans generally followed the longstanding tradition of using hachures—short parallel lines, a form of shading. Denser steeper lines were darker, indicating steeper slopes. Map readers found these "terrestrial maps" intuitive. Hachures were considered natural symbols for representing mountains, their locations, and their sinuousities.

Clarence King’s Topographical Map of Central California Together With a Part of Nevada (1873), in hachures.

Hachured mountains from King’s 1873 map; lake upper right is marked with waterlines—parallel lines decreasing in density away from shore.

However, hachured maps lacked precision and even basic information. While they showed location and shape of mountains ranges, distances and especially elevations were little more than suggestions. “They give us only a mutilated image of the land” (source).

Fortunately there was an alternative—contour lines, which connect points of equal elevation. Like hachures they show shape and slope, but with much greater precision.

Where contour lines are closer together, the slope is steeper (USGS 1897, from source).

Contour lines had been around since sometime in the 1700s, but were slow to be widely adopted. Many map users found them confusing. British soldiers are said to have objected, complaining that the lines were difficult to read while hachures were intuitive. Indeed, contour lines are abstract compared to hachures, requiring a greater cognitive leap. But with proper survey, they can provide a wealth of accurate information. 

For Gannett, the decision was easy: the USGS would use contour lines. To assist with transitioning from hachures, early maps often included shaded relief (aka hill shading).

Contour lines with shaded relief (sunlight always comes from the northwest).

Gannett also was forward-thinking with regards to map quality. USGS maps would be printed using lithographic stones, multiple colors, and one of the best color lithography firms in the US.

At that time, most maps were printed directly from metal plates, usually copper. Following the surveyor’s sketched map and data, a skilled engraver cut lines and points into a plate. Copper is suitable for engraving, being relatively soft, but for the same reason, engraved plates became worn with use.

“With great precision, an engraver carefully cuts away small ribbons of copper" (USGS).

“Tools of the trade ... the burin and the hand lens, resting on a contours engraving” (USGS).

The USGS did use copper plates, but NOT to print maps directly. Instead, the engraving was transferred from the plate to a much more durable lithographic stone. The process was complex. Below are step-by-step instructions, in brief (more information here):

• From a surveyor’s sketched map and data, engrave a copper plate.

• Ink the plate and lay a paper sheet on it.

• Press.

• Check print for errors, fix copper plate, make another print, continue until satisfactory.

• Transfer printed map image to lithographic stone using grease pencils, gum arabic and nitric acid (!).

• Ink the stone and lay a paper sheet on it.

• Press.

• Remove paper sheet from plate. Voilá—a map!

Repeat the last three steps for as many copies as are needed UNLESS ... the map has multiple colors. Then one must print EACH map with multiple stones, one per color!

A map "typically required 3 individual lithographic stones for printing, one for each color” (USGS). When the map was moved to the next stone, alignment was critical.

Colors typically used for USGS maps were brown (contour lines and shading), blue (water features) and black (cultural features such as towns and railroads). We see this in Russell’s maps, but with one obvious difference. Two shades of blue were needed, to distinguish lakes past and present.

Today’s small scattered lakes are pale blue; ancient Lake Lahontan is darker; darkest areas are playas (from Plate XLVI).

This complicated process of color printing could not be done in house. Instead, the government contracted with specialists, often Julius Bien & Company. Bien was a pioneer in chromolithography, and his scientific approach to printing made his products exceptional (5). Bien & Company produced many maps for the US government—for Pacific Railroad Surveys, the census, coast surveys, the topographic surveys of the USGS and more.

All color maps in Monograph XI bear the imprint "Julius Bien & Co. Lith."

The more I looked Russell’s monograph and maps, and the more I learned about the cartography and printing involved, the more I wondered … How did a costly science project like this get funded by the federal government, especially during the Gilded Age—a time better known for concentrated wealth, widespread poverty and government corruption.

It was funded thanks to John Wesley Powell, famous for his descent of the Colorado River through the Grand Canyon. He spent his later life in Washington, DC, much of it as Director of the US Geological Survey. Powell knew how to make things happen. He knew the right people, and how to lobby effectively. He even knew the best brand of cigars to hand out as gifts (Worster 2002). And in his requests for funding, he wisely slipped scientific studies—Ice Age lakes and such—in with mandated economic geology projects, chiefly surveys of mining districts. We who love the natural history of the American West are so grateful!

Our hero, with headman Tau-gu, c. 1873 (NPS).

Notes

(1) Russell’s first field season was a solo reconnaissance. During the next two he was assisted at various times by cartographers AL Webster and WD Johnson, and geologists WJ McGee and GM Wright. For more, see "Back to Lake Lahontan ..."

(2) The Government Printing Office is now "Government Publishing Office". 

(3) Sales were overseen by the Superintendent of Documents starting in 1895.

(4) I think I know the reason for the reasonable price. Plate XLVI, said to inhabit the Map Pocket, is missing. In fact, the map pocket on the inside back cover is pristine—perfectly flat and tight, never been used. And at 20 × 32 inches, the map wouldn't fit in that pocket no matter how it was folded. So I downloaded a file from the Rumsey collection and had it printed at the UPS Store.

(5) Julius Bien was a German-Jewish immigrant who fled the failed 1848 revolution. He went on to build one of the preeminent lithography firms in the United States. See Julius Bien, Master Printer and Cartographer for more about this man and his maps.

Sources (in addition to links in post)

Churchill, C. 2025. Variety in hachure. Carl Churchill Blog.

David Rumsey Historical Map Collection (DRHMC). Plate XLVI: Lake Lahontan : a quaternary lake of northwestern Nevada; Media Information. Accessed September 2026. [Many maps in this post are from the wonderful Rumsey collection.]

Edney, M. 2018. USGS printing techniques. Mapping as Process (blog).

Hacker, C. Depicting the Landscape - Part 2. in Cartographic Symbologies, The Art and Design of Expression in Historic Maps. Stanford University Libraries. Accessed September 2026.

NVG. Historical Printing Techniques, Intaglio, in Women’s Work. The Linda Hall. Accessed September 2026.

Raines, A. 2024. Fabricating the World: Copperplate Printing, in WORLDS REVEALED, Geography & Maps at the Library of Congress.

Russell, IC. 1885. Geological history of Lake Lahontan. USGS Monograph 11.

Worster, D. 2002. A River Running West, the life of John Wesley Powell. Oxford University Press.

The Monthly Orchid: What do you get when you cross a Coralroot & a wasp?

Answer: Capsules filled with seeds! (Striped Coralroot, Awinch1001)

Welcome back to the The Monthly Orchid, a series about South Dakota's native orchids. This month we again look at Coralroots, specifically the Striped Coralroot, Corallorhiza striata. Coralroots aren't particularly showy, but this one is a bit of an exception. Though the lip petal is small, its stripes are bold. Might they have a purpose? To this, Charles Darwin would reply with an emphatic "Yes!"

Corallorhiza striata; note yellow pollen positioned above base of lip (Freudenstein & Barrett 2026).

Darwin was fascinated by orchid flowers, largely because "the contrivances by which Orchids are fertilised are as varied and almost as perfect as any of the most beautiful adaptations in the animal kingdom." In this diversity, he saw an opportunity to respond to criticism of On the Origin of Species, which he published in 1859.

Just a few years later, Darwin finished another book—The Various Contrivances by which Orchids are Fertilised (1862). In the Introduction, he explained the purpose of his "little treatise" (c. 300 pages):

"Having been blamed for propounding [natural selection] without giving ample facts, for which I had not sufficient space in that work, I wish here to show that I have not spoken without having gone into details."

A myth Darwin intended to debunk was the notion that orchid beauty is "the result of the direct interposition of the Creator" for the pleasure of humans. Wrong! Beautiful orchid flowers are the result of natural selection, and like the vast majority of flowers, they have one purpose—continuation of the species, via sex. 

Why such varied and gorgeous lips? From Kunstformen der Natur, E. Haeckel, 1899.

In last month's post, a Coralroot seed encountered just the right underground fungus, germinated, started to grow, and emerged from the Underworld. We left it surviving on carbon captured by trees and shared (involuntarily) by the fungus. What next? At some point we should see buds, followed by flowers, and then capsules with seeds. Must the fungus help with all this as well? Aside from providing sustenance for growth, the answer is "No". In the case of the Striped Coralroot, however, dependency continues. Now another type of creature will be will be duped.

For most flowing plants (angiosperms), pollination is required to produce seeds. This is what drove evolution of the astonishing diversity in orchid flowers.

South Dakota orchids: Helleborine, Yellow Lady's Slipper, Prairie Fringed Orchid; note the varied contrivances.

With many examples (1), detailed descriptions and lengthy discussion, Darwin was able to argue convincingly that most orchids are designed with insects in mind.

"these contrivances have for their main object the fertilisation of the flowers with pollen brought by insects ... In almost all the species, one of the petals, which is the properly upper one, is larger than the others and stands on the lower side of the flower, where it offers a landing-place for insects, having been carried round by the twisting of the ovarium (2). It is called the lower lip or labellum, and often assumes most singular shapes." (italics mine)

In addition to specialized lips, orchids employ a variety of strategies to lure pollinators (Ackerman et al. 2023; Wikipedia). The most common is attraction by means of reward, e.g., nectar, oil, perfumes. These are given in exchange for pollen transport—arrival from or delivery to another orchid of the same kind. Flower shape, color pattern, and scent are commonly used to attract a specific pollinator, reducing the chance that pollen is wasted on the wrong orchid. 

But many orchids are not so nice. At least a third of the 30,000 known species rely on deception to attract pollinators. Having become highly specialized through natural selection, they are very good at this. Here are some examples.

• An orchid that provides no nourishment has flowers very similar to those of a plant that does. This is feeding deception, the most common type of deceptive pollination. 

• In brood-site deception, an orchid's flowers look like perfect egg-laying sites to the pollinator (see next photo). 

• Even more remarkable is pseudo-antagonism, in which a flower mimics an enemy of the pollinator, invoking an attack during which pollen is transferred!

Cypripedium lichiangense, the Lijiang Cypripedium (Steve Garvie). It offers an appealing (stinky!) but fake brood-site for Ferdinandea cuprea, a hoverfly (Ackerman 2023).

The most fascinating strategy (based on number of studies and websites) appears to be sexual deception, or pseudocopulation. It's the second most common type of deceptive pollination in orchids, documented in at least 22 genera (Ackerman 2023). Perhaps you have already guessed—Striped Coralroot is a sexually deceptive orchid! In fact, it's the first example of a pseudocopulatory orchid from North America!! (Freudenstein & Barrett 2026)

Corallorhiza striata, Andrey Zharkikh.

Freudenstein and Barrett used an insect net to capture wasps visiting Striped Coralroot flowers. They sexed them by looking for a prominent ovipositor. All 28 were male. Another 13 males were captured and sexed in photographs. The researchers then probed 30 of the flowers visited, and found no nectar. 

To determine what was attracting the wasps, they opened a plastic bag of Striped Coralroot flowers inside a net cone, hoping to release volatile scent compounds. Sure enough, within two minutes a swarm of 10 wasps appeared, flew around the cone, and landed on it (they couldn't get to the flowers).

And the stripes? The authors found no obvious resemblance between flowers and female wasps, but the "red stripe down the center [of the lip] flanked by two lighter patches could signal a wasp metasoma" (a body segment). I wonder—how might one test this hypothesis?

Whatever the attraction, all visiting wasps were the same kind—Pimpla pedalis, which is parasitic on the Pale-Winged Gray, a moth that defoliates Eastern Hemlock. In other words, the orchid dupes a wasp that is parasitic on the larvae of a moth that harms trees. Go Coralroot! (3)

If you are unable to view Pimpla pedalis "mating" with Corallorhiza striata (above), go to Freudenstein & Barrett 2026 (open access) and download the video in Supporting Information at the bottom of the page. Or try this video narrated by David Attenborough. It includes neither Striped Coralroot nor Pimpla pedalis, but is quite entertaining!

Now it's time to leave the Coralroots and move on to orchids with morals as well as beauty, perhaps Cypripedium (Lady's Slippers).

"As Orchids are universally acknowledged to rank amongst the most singular and most modified forms in the vegetable kingdom ... examination of their many beautiful contrivances will exalt the whole vegetable kingdom in most persons' estimation." (Darwin 1862, italics mine)

Cypripedium (Darwin 1862).

Notes

(1) Darwin's book includes exotic as well as British orchids. He received many specimens after reaching out to colleagues and collectors.

(2) Darwin is referring to resupination, which is common in orchid flowers. In bud, the lip petal is oriented upward, but by the time the flower opens, the ovary (sometimes the flower stalk) has twisted enough to orient the lip downward. See The Upside Down World of Orchids.

(3) In the orchid's ruse, Freudenstein and Barrett saw the opportunity for an especially alluring title: "Corallorhiza striata is the first example of a pseudocopulatory orchid in North America and an instance of 'double deception' in fully mycoheterotrophic plants." Wow, that's so cool! But wait ... is this really double deception? That depends on your opinion of Coralroots after reading last month's post.


Sources (in addition to links in post)

Ackerman, JD, et al. 2023. Beyond the various contrivances by which orchids are pollinated: global patterns in orchid pollination biology. Botanical Journal of the Linnean Society 202:295–324. https://doi.org/10.1093/botlinnean/boac082 

Britannica. Orchid/natural history/pollination. Accessed August 2026.

Darwin, Charles. 1862 (1904, 7th printing of 2nd edition). The Various Contrivances by Which Orchids Are Fertilised by Insects. London: J. Murray. https://doi.org/10.5962/bhl.title.84436

Freudenstein, JV, and Barrett, CF. 2026. Corallorhiza striata is the first example of a pseudocopulatory orchid in North America and an instance of“double deception” in fully mycoheterotrophic plants. American Journal of Botany 113(4): e70185. https://doi.org/10.1002/ajb2.70185

USDA Forest Service. Coralroot Orchids. The Celebrating Wildflowers—Beauty of It All website is a joy to wander through! I wish I knew whom to credit for it.