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Items starting with I


A parcel of land in other ownership (State, private, other Federal agency) surrounded by National Forest System land.

Initial attack

This term applies to an aggressive suppression action consistent with firefighter and public safety and with protecting various resource values.

Instream Flow

The quantity of water necessary to meet seasonal stream flow requirements to accomplish the purposes of the National Forests, including, but not limited to fisheries, visual quality, and recreational opportunities.

Integrated Pest Management (IPM)

IPM evaluates alternatives for managing forest pest populations, based on consideration of pest-host relationships.

Interim Management Policy

The BLM management policy for lands under Wilderness review which lays out the requirements for management of WSA's so as to not impair their suitability as wilderness.

Intermediate Cut

The removal of trees from a stand sometime between the beginning or formation of the stand and the regeneration cut. Types of intermediate cuts include thinning, release, and improvement cuttings.

Intermountain Region

The portion of the USDA Forest Service, also referred to as Region Four, that includes National Forests in Utah, Nevada, southern Idaho, and southwestern Wyoming.

Invasive species

A species that is 1) nonnative (or alien) to the ecosystem under consideration, and 2) whose introduction causes, or is likely to cause, economic or environmental harm or harm to human health.