Rubber Made

I'm reading Edison's Eve: A Magical History of the Quest for Mechanical Life. It's an interesting historical glimpse into exploits of inventor Thomas Edison, among others. One of the more fascinating tidbits I just learned is that the yellow, flowering goldenrod is a naturally-occurring American source of rubber.

Naturally, we don't use it in the manufacturing process as this passage from American Heritage explains [bolding is mine].

Oddly enough, not only Edison, but Henry Ford, the Du Pont company, and Standard Oil of New Jersey, after 1925 had received information about the new German chemical process for converting coal or petroleum derivatives into synthetic rubber of the butadiene and sodium type, which was already perfected by the I. G. Farben Gesellschaft around that time. But large-scale operations were not to be carried out until a decade later, prior to World War II.

Edison also might have turned his eyes in this direction—which was to be the most profitable for systematic research but for the fact that the synthetic process was known to require an enormous investment in special chemical plants, which even our biggest rubber tire and chemical corporations refused to risk at that period.

In 1940 federal government subsidies alone would make synthetic rubber production feasible. In that year government scientists thoroughly explored the alternate possibilities of using organic materials available to us, such as Edison’s variety of goldenrod and guayule, but reached the conclusion that processing such plants would be more difficult and costly than making a synthetic, and would yield a product inferior to natural India rubber or the new synthetics.