https://www.britannica.com/topic/Earth-First

Earth First! was widely known for its tactics. It generally eschewed the lobbying and political deal-making associated with mainstream environmental organizations. Instead, its activists typically engaged in nonviolent direct action, such as civil disobedience to block environmentally harmful activities and “monkeywrenching” (the sabotage of machinery involved in environmental destruction). In the first years after the group’s formation, the use of direct actions—standing in front of bulldozers and putting spikes (e.g., metal rods or nails) in trees to prevent them from being cut—brought national news coverage to Earth First!. The group subsequently grew.