Goldenrod and Science, Part 1 - Industry

Wildflowers, weeds, economic resource?  Goldenrod plants, which comprise the genus Solidago, have attracted diverse attention from people. Opinions are in the eye of the beholder.

Scientific analysis has freed it from blame as an allergy irritant. Goldenrod depends on insects to pollinate its flowers. The flowers' pollen grains are too heavy to drift in the air toward your sinuses.

Tall goldenrod, Solidago altissima,
which can exceed six feet of height in moist areas of Halibut Point

Further examination reveals that goldenrod contains a significant amount of latex, which is produced by about 10% of flowering plant species. Latex is believed to serve as a defense against insect infestation. It is stored in cells just underneath the outer layer of each part of the goldenrod plant. You might have noticed a similar substance as the milky white fluid that bleeds from a plucked dandelion stem. Tiny particles of the natural rubber polymer polyisoprene are suspended in the latex. ¹

L to R: Henry Ford, Thomas Edison, Harvey Firestone ²

A century ago three of the most inventive industrialists in America, who happened to be close friends, began searching for alternative sources to imported rubber. In part they were concerned with the nation's dependence on foreign resources during wartime. Henry Ford, Thomas Edison, and Harvey Firestone contributed $25,000 apiece In 1927 to form the Edison Botanic Research Corporation. Thomas Edison, the restless mind behind the electric light bulb, the phonograph, and the motion picture camera, holder of over 1,000 patents, launched a new pursuit at his winter home in Fort Meyers, Florida. ²

Thomas Edison standing in a field of goldenrod, 1929 ³

Edison invited botanists from around the world to send plants with promising latex content for analysis. His laboratory staff ground the samples and chemically treated them to determine available rubber. They analyzed more than 17,000 plant samples. Solidago was selected as the most promising group, for its high rubber content and its quick growth performance in the United States. ⁴

Edison and goldenrod specimen ²

Edison finally settled on a particular species of goldenrod, Solidago elliottii. He developed a cultivar to grow over ten feet tall with an improved rubber yield. This selection was later named after him, Solidago edisoniana. ⁵

A sample of goldenrod rubber at Edison's laboratory ¹

The photograph above shows "crude" goldenrod rubber after the polymer particles have been coagulated and separated out of the latex, which is mostly water. Below is a strip of goldenrod rubber compounded with carbon particles for strength, ready to be formed into a tire.

A rubber strip made from goldenrod ¹

Harvey Firestone did produce a set of goldenrod rubber tires for Edison's 1907 Model T Ford, a cherished possession given to him by his friend, Henry Ford. ⁶

After Edison's death in 1931 Ford spearheaded the quest. He corresponded with George Washington Carver in 1935, the innovative plant hybridizer at Tuskegee Institute in Alabama. As their relationship deepened productively, they traveled to each other's facilities. Ford sought to develop auto body materials, paint, and engine fuels derived from farming staples. They collaborated on the goldenrod latex project. Ultimately it was supplanted by more practical processes deriving synthetic rubber from petroleum.

George Washington Carver (L) and Henry Ford, 1942 ⁷

Ford and Carver both believed that the American farm was at the core of industry. They promoted “chemurgy,” a branch of science merging agriculture and industry with a central tenet that farms played an important part in the society and should not be lost to industrialization. ⁸  In 1942 Henry Ford showed his admiration for his friend and colleague by naming a new Ford Motor Company facility in Dearborn, Michigan, The George Washington Carver Nutrition Laboratory.

Sources

1. "Thomas Edison, Botanist," blog Kind ofCurious.com, November 29, 2010.
2. "Thomas Edison, The Rubber Wizard of Menlo Park?", Stern Rubber Company blog, August 20, 2015.
3.  "Thomas Edison Experimenting with Goldenrod as an Alternative Source of Rubber, Florida, 1929", TheHenryFord.org website.
4. "Thomas Edison, Chemist", American Chemistry Society website acs.org, 2019.
5. "In Search of Thomas Edison's Botanic Treasures", New York Botanical Garden Herbarium, posted in Applied Science website, October 30, 2013.
6. "Phonograph Exhibit Hints at Rubber Invention", The Orlando Sentinel, October 4, 1992.
7. Photo taken in The Carver Nutrition Laboratory, Dearborn Michigan, 1942, TheHenryFord.org website.
8. "Soybean and Weeds Sandwiches: George Washington Carver and Henry Ford at the Tuskegee Institute", The History Engine website.