Tree spiking

Tree spiking involves hammering a metal rod, nail, or other material into a tree trunk, either 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 saw mill later processing the wood. It is a tactic used to discourage logging, either by creating a mantrap which may injure or kill lumberjacks who attempt to cut down the tree, or to damage the sawmill equipment later processing the wood. (Commonly spikes are placed in areas above the base in order to bypass initial spike inspections. This form of tree spiking is not intended to harm loggers, it is designed to slow down sawmill production.) Furthermore, the presence of the spike reduces the commercial value of the wood by causing discoloration, thereby reducing the economic viability of logging in the long term, while not threatening the life of the tree.

It is believed that tree spiking originated in timber logging labor disputes in the Pacific Northwest of the United States in the late 19th century. It came to prominence as a contentious tactic within unconventional environmentalist circles 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.