Land Use Change

Criteria: Land Use Change

Data Source: USDA Forest Service FIA
Last Updated: March 2019

 

WHY LAND USE CHANGE? 

Keeping “forests as forests” is important for a variety of reasons. Forests provide habitat for plant and animal species, they enhance soil, purify our water and air, help to sequester carbon dioxide from the atmosphere, and much more. When forest land is converted (e.g. for agriculture and development) to other non-forest uses, a loss of important services and functions may occur.

This criterion helps our members understand what land uses may contribute to forest loss and/or forest conversion.

 

SUMMARY

This criterion estimates the percent net change of [land classified as] timberlands within the geography of interest, over a five-year period.  Where timberland change (loss or gain) occurs, we indicate which land-use types this change can most likely be attributed to:  

• Agriculture: row crops, such as soy, cotton, etc.
• Development: housing or commercial development, etc.
• Other: transitions to lower density forests (which are unlikely to be supply mills), water encroachment, and conversion to rangeland.

 

RISK THRESHOLDS

	LOWER RISK	MEDIUM RISK	HIGHER RISK
Land Use Change	Less than or equal to 1% net loss of timberland annually, or a 5% net loss over a five-year period.	Between 1% to 2% net loss of timberland annually, or a 5% to 10% net loss over a five-year period.	More than 2% net loss of timberland annually, or a 10% net loss over a five-year period.

 

TECHNICAL INFORMATION

The Land Use Change criterion uses data from the USDA Forest Service’s Forest Inventory and Analysis (FIA). The FIA is an ongoing census that reports on status and trends in forest area and location; in the species, size, and health of trees; in total tree growth, mortality, and removals by harvest; in wood production and utilization rates by various products; and in forest land ownership. Forests in Focus also uses the FIA designation of “timberland” to standardize how we define forests across the USA. Timberland is forest land that is at least one acre, not legally withdrawn from timber production, and that is capable of producing more than 20 cubic feet per acre per year of [industrial] wood. 

 

POSSIBLE DATA AND ANALYSIS LIMITATIONS

As a result of differences in the methodology used to scale data (from plot to Hexagon or from plots to Assessment Area), percent and net change results may differ slightly between the Assessment Area Dashboard and Summary Dashboard.

The FIA methodology we utilize is designed to support an understanding of the nation’s forest resource and to support observations about trends at different scales. As with any analysis, there are statistical limitations to results, especially at finer scales. FIA data plots, for example, may not be evenly distributed across a landscape, which may affect statistical reliability in the case of a small sample size. Furthermore, several states including Wyoming, New Mexico and Nevada were not included in the Forests in Focus assessment, as the FIA data was insufficient to provide calculations consistent with the other states.