This article considers how, and under what conditions, actors in irregular conflicts weaponize nature. When do insurgents and counterinsurgents pursue environmental degradation—ranging from limited and short-term damage to ecocidal violence—as a tactic of war? To what extent do we see variation in the frequency and form of environmental warfare? And when do conflict actors exercise restraint in their use of violence against the natural environment? Often, the intentional destruction of the natural landscape is difficult to explain by reference to operational strategy or tactical logic alone. Deliberate attacks on the natural landscape, the frequency with which these tactics are deployed, and the diverse forms they take are conditioned by context-specific incentives, constraints, and intervening variables. I identify six categories of incentives and constraints that influence the decision to engage in environmental destruction: strategic, tactical, political, ideological, cultural, and technological. Using suggestive evidence from multiple case studies, I theorize some possible interactions between incentives and constraints that help to explain variation in the form and frequency of environmental warfare tactics.