Racing tires made from desert shrubs in Pinal County debut before Indy 500 as Bridgestone Americas revs up production

Jeff Kronenfeld
Firestone Firehawk racing tire made from guayule-derived rubber.(Bridgestone Americas)

By Jeff Kronenfeld / NewsBreak Pinal County, AZ

(Pinal County, AZ) Bridgestone Americas’ guayule-derived natural rubber meets the road at the Indy 500 Pit Stop Challenge on May 27.

The green side walled racing tires are the latest advance in the effort to make Pinal County the epicenter of a new domestic rubber industry based on a drought-resistant shrub — guayule —native to the Southwest's Chihuahua Desert.

The company received a boost in March when the Department of Energy Joint Genome Institute awarded them a grant to explore the genetics of three guayule varieties to increase rubber yields.

By 2027, the company plans to open a commercial production facility for guayule rubber in Mesa.

It will require roughly 80,000 acres of guayule to support operations, with most of that expected to be grown in Pinal County, according to David Dierig, section manager of Bridgestone’s Agricultural Operations Guayule Research Farm in Eloy.

“We're going to have to start scaling up the crop in 2024, ‘25, and ‘26 to be able to have the amount of shrubs that we need for extraction in 2027,” Dierig explained.
A field of guayule at the Agricultural Operations Guayule Research Farm in Eloy.(Bridgestone Americas)

The rubber shrub

Bridgestone wasn’t the first to attempt tapping guayule as a domestic source of rubber.

The US government planted somewhere between 20,000 to 30,000 acres of guayule during World War II. However, that program never harvested the crops due to the war's end and growing interest in synthetic rubber.

The government tried commercializing guayule again in the 70s and 80s, but these efforts failed to pan out either.

Bridgestone got in the game in 2012 when it broke ground on a 281-acre guayule research farm in Eloy and the Bio­rubber Process Research Center in Mesa. Three years later, the company produced its first tire from guayule rubber.

They succeeded where previous attempts failed due to advances in three areas.

“One is improving the plant genetics, so the breeding genetics part,” explained Dierig. “And then the second is developing the agronomic management tools for it. So, figuring out how much water it's going to take, how much fertilizer it needs, what kind of controls we need for insects and for weeds. And then the third part is how do we start establishing relationships with growers.”
A guayule plant at the Agricultural Operations Guayule Research Farm in Eloy.(Bridgestone Americas)

Desert plants for desert farms

For Pinal County growers facing historic cuts to their water supply, guayule's desert adaptations offer several benefits.

The plant’s leaves have hairs known as pubescence and a waxy outer layer that help it preserve water, while a deep taproot lets it access moisture other crops can’t reach.

All this means Guayule uses significantly less water than cotton or alfalfa. Further, the hardy shrub can survive interruptions to its watering schedule that would kill more finicky crops.

Guayule also needs fewer pesticides and herbicides due to the mature plant naturally repelling insects and being able to resist encroaching weeds.

Another benefit of the desert shrub is that it needs less tilling, reducing soil erosion and increasing the amount of carbon it captures.

Still, Dierig does encounter resistance from some farmers.

“What growers usually have difficulty with is that it's a perennial crop, not an annual crop,” he explained. “It’s just that they haven't grown anything like it, and so, it's getting growers educated about trying something new and being able to work with a small, seeded crop.”

Despite such challenges, the company predicts local farmers will add 200 new acres of guayule by year’s end.
The Agricultural Operations Guayule Research Farm in Eloy.(Bridgestone Americas)

Rubber, latex, bio-pesticides, and more

Guayule rubber is chemically the same as rubber from rubber trees, so you shouldn’t notice a difference in smell when the Firestone Firehawk race tires made from guayule peel out in Indianapolis this week.

The first Tag Heuer Indy 500 Pit Stop Challenge occurred in 1977. The short race casts the limelight on pit crews during the lead-up to the Indianapolis 500. Bridgestone hopes to draw attention to guayule by participating in this nationally televised event.

The tires make their competition debut at the Big Machine Music City Grand Prix in Nashville in August.

While Bridgestone is primarily interested in guayule for producing rubber, the plant can yield many other products, like hypoallergenic latex suitable for gloves, medical products, and prophylactics.

Guayule resin can produce a bio-pesticide and an adhesive. Even the remaining woody material is useable as burnable pellets or biofuel.
David Dierig, section manager of Bridgestone’s Agricultural Operations Guayule Research Farm in Eloy.(Bridgestone Americas)

Looking forward

Dierig foresees the growing guayule industry's potentially significant impact on Pinal County and beyond.

“It's really the first of its kind in the world,” Dierig explained. “The plan is just to take that as a template and open other facilities across the Southwest. More in Arizona and others in Texas and New Mexico.”

He encourages farmers interested in learning more about guayule to reach out directly by email.

Comments / 1

Published by

Jeff is an award-winning freelance journalist covering news, business, science and the arts. His work has been published in Discover Magazine, Vice, the Phoenix New Times and other outlets.

Tempe, AZ

More from Jeff Kronenfeld

Comments / 0