More than two dozen companies, cities, and organizations are embracing a pledge to help plant 1 trillion trees, a tactic to curb climate change that has even President Trump’s blessing.

Altogether, the participants will plant, restore, and conserve more than 855 million trees in the United States by 2030. Their pledges form the basis of the U.S. chapter of the “1 Trillion Trees” initiative, or 1t.org, the first nationwide effort to make the goal a reality.