Spike involves hammering a metal rod, nail, or other material into a tree trunk, or inserting it at the base of the trunk where a logger might be expected to cut into the tree, or higher up where it would affect the sawmill later processing the wood. It is used to prevent logging by the forest, in the forest or at the mill, if the tree is cut. The cause of discoloration, the reduction of economic viability of logging in the long term, without threatening the life of the tree.
It is believed that it originated in the Pacific Northwest from the United States in the late 19th century [ citation needed ] . It came to prominence as a tactical contentious within environmental conventions during the 1980s, after it was advocated by Earth First! co-founder Dave Foreman in his book Ecodefense . In the book, he discusses how to do it and how to avoid risks to the activist and the logger.
In 1987 California mill worker George Alexander gravement Was Injured When the bandsaw He Was Either operating Was shattered by an old nail or spike a tree. This led the leader of Earth First! to denounce tree spiking. 
Other activists [ citation needed ] were led to this form of sabotage entirely, or to take precautions, such as putting warning signs in the area where the trees are being spiked. Tree spiking is Condemned by Opponents of eco-terrorismWho claim it is Potentially dangerous to loggers or mill-workers,  ALTHOUGH only this one injury resulting and from tree spiking has-been reported. 
Beech trees that were being logged in 1998 in the Tuatapere area were spiked. Police were unable to trace those who were responsible. 
Pat O’Dea , while he was the mayor for the Buller District, suggested in 2000 that Native Forest Action (NFA) had spiked trees during a direct action campaign against native forest logging on the West Coast .  This was denied by NFA spokesperson Dean Bagient-Mercer.  In 1998, Kevin Smith of Forest and Bird, said that the NFA campaign was one of the few. 
Following the 1987 injury of California mill worker George Alexander, tree spying was declared a federal felony in the United States in 1988. ( 18 U.S. Code 1864).
In 1990, Earth First! leader Judi Bari led activists in Southern California and Southern Oregon to renounce tree-spiking as a tactic on the eve of Redwood Summer , a 1990 campaign of nonviolent protests against the logging of the redwood forest . 
- Tree sitting
- ^ Jump up to:a b Rowell, Andrew (1996). Green Backlash . Routledge. p. 153. ISBN 9780415128285 .
- Jump up^ Ecoterrorism: The Dangerous Fringe of the Environmental Movement
- ^ Jump up to:a b Nixon, Tina (1998-01-06). “Spikes put workers’ lives at risk”. The Southland Times.
- Jump up^ Madgwick, Paul (2000-04-14). “Public backlash around NZ feared”. The Press .
- Jump up^ Bagient-Mercer, Dean (2000-04-27). “West Coast forests”. Letter to the Editor . The Press .
- Jump up^ “Tree-spiking renunciation & Mississippi summer in the California redwoods”