Hulkenberg only driver to skip Vettel’s tree project

Only one of the 20 Formula 1 drivers took part in his latest environmental initiative in Brazil - with only Nico Hulkenberg opting out.

The four-time world champion returned to the Sao Paulo paddock last weekend to promote rainforest protection, setting up a stand where drivers, team bosses and guests were invited to draw a tree as part of his awareness campaign.

According to Auto Motor und Sport, everyone supported the idea - except fellow German Hulkenberg.

The Sauber driver, who at 38 is also the same age as his retired countryman, personally informed Vettel that he would not take part, citing focus and routine during an intense Grand Prix weekend.

There was no animosity behind the decision, the magazine added, and Vettel himself made it clear he took no offence.

Vettel did, however, highlight the lack of public activism among most drivers - singling out one exception.

"Lewis is the only driver on the grid who speaks out publicly on certain issues," he said. "We have a close relationship and exchange ideas regularly."

He admitted some regret about not embracing such advocacy earlier in his career.

"If there’s anything I regret, it’s realising too late that you can inspire people with issues close to your heart," he said. "Maybe drivers should listen more to that inner voice."