Welcome to Umpqua Watersheds' Glossary. This page was developed by downloading the Forest Service's glossary, then adding and deleting relevant/non-relevant items, and modifying some of their interpretations of other terms. If you don't see something here you need, or disagree with a definition, please contact Umpqua Watersheds, Inc.

Glossary   A

Adaptive Management Areas (AMA)

An Option 9 designation for certain lands in the National Forests. In the Umpqua NF, our AMA straddles the North Umpqua Ranger District of the UNF, and the Scott Resource Area of the BLM. Our AMA is in an area of hammered watersheds (lots of clear-cuts). The Option 9 definition of an AMA is: "Adaptive Management Areas are landscape units designated to encourage the development and testing of technical and social approaches to achieving desired ecological, economic, and other social objectives." In other words, the local community is supposed to have a greater say in what happens there, and its objective is to test other Option 9 land designations (such as matrix) as to the effect of allowable management activities on the ecosystem. Our AMA called "Little River AMA" is 91,800 acres, and is one of 10 AMA's in the range of the spotted owl. Each has their own emphasis. Ours is: "Development and testing of approaches to integration of intensive timber production with restoration and maintenance of high quality riparian habitat." We've all asked ourselves - How can we have 'intensive timber production' and 'high quality riparian habitat'?

AWA - Administratively Withdrawn Areas

Lands identified in current forest and district pans that include recreational areas and areas not suitable for timber harvest.

Aerial logging

Removing logs from a timber harvest area by helicopter.

Age class

An age grouping of trees according to an interval of years, usually 20 years. A single age class would have trees that are within 20 years of the same age, such as 1-20 years or 21-40 years.

Allotment (range allotment)

The area designated for use by a prescribed number of livestock for a prescribed period of time. An entire Ranger District may be divided into allotments for grazing.

Anadromous fish

Species of fish that mature in the sea and migrate into streams to spawn. Most species are now endangered; the Umpqua cutthroat trout is an example.

Aquatic Conservation Strategy

A component of the Northwest Forest Plan. Designed to resore and maintain the ecological health of watersheds and aquatic ecosystems.

Area of Critical Environmental Concern (ACEC)

Lands where special management attention is needed to protect and prevent damage to important historic, cultural, or scenic values, fish, and wildlife resources or other natural systems or processes or to protect life and provide safety from natural hazards.

Aspect

The direction a slope faces. A hillside facing east has an eastern aspect.

ASQ (allowable sale quantity)

The amount of timber that may be sold within a certain time period from an area. The areas and the time period are specified in the Forest Plan.

AUM (animal unit month)

The quantity of forage required by one mature cow and her calf (or the equivalent, in sheep or horses, for instance) for one month.