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Forest Inventory and Analysis Program of the U.S. Department of Agriculture

Michael Williams and Gretchen Moisen

Intermountain West Forest Inventory and Analysis

Ogden, Utah

Ken Winterberger

Pacific Northwest Forest Inventory and Analysis

Anchorage, Alaska

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What is FIA? “The Census program for the Nation’s

Forest Lands” One of the oldest continuous natural

resource inventories (since 1928) One of the largest natural resource

inventories in the world (3,537,441 square miles=2.26 billion acres)

Ground-based data collection Collects information for all “forest” land

and ownerships

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Forest land is diverse

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Diverse Ownerships

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FIA Outputs and Issues

Current status and trend of U.S. forests Maps Carbon sequestration, climate change Criterion Indicators Fire/Fuels Ozone damage and acid rain Habitat ………

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Topics for Discussion

How FIA has changed The “base” FIA program (P2) Integration of Forest Health

Monitoring (P3) Filling in the “base”

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Part I: The base FIA

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The Big Change for FIAPre 1998 Post 1998

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Summary of Changes

Periodic survey Slightly Different

Sampling Rates Regional Plot Regional Field

Manuals Different Database

and Analysis Programs

Different Estimation Methods

Annual Panel survey

Standard Plot Standard Data

Collection Methods “core variables”

Common Database

Post 1998Pre 1998

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Goals of the New FIA Program

Create a Nationally Consistent Survey (spatial and temporal)

Improved timeliness of information Minimize disruptions (can’t start over) Integrate FIA with Forest Health Monitoring

(FHM) Meet data needs of our diverse group of

customers

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Goal 1. Spatial Consistency

Consistent “base” sampling rate of ~ 1 plot / 6000 acres

Utilize as many existing sample locations as possible

Be able to change sampling intensity to meet regional goals

Integrate with existing Forest Health Monitoring program

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Hexagon tessellation of a sphere

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Change hexagon size by subdividing nodes with triangles

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FHM grid of Wyoming (1hex~160,000 acres)

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Hexagons for FHM and FIA (1 FHM hex ~ 27 FIA hexagons)

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Plots selection rules 1.  if the FIA hexagon contained an FHM

plot, the existing FHM plot was selected; 2.  if not, then an existing FIA plot was

selected; 3.  if there were multiple FIA plots in the

hexagon, the one closest to hexagon center was selected and the others were abandoned;

4.  if there were no existing FHM or FIA plots in the hexagon, a new sample location was selected based on a random azimuth and distance from hexagon center.

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Example of 1 plot/hex

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Temporal Considerations Non-overlapping panel survey (i.e., measure

x % of all plots every year) Annual coverage of all large-scale events

(e.g., assess hurricane impact) Ability to change the cycle length Sub-paneling

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Temporal patterns

Hexagon panel assignments illustrating the parallelogram pattern of a 5-panel rotation.

Hexagon panel assignments illustrating

the triangular pattern of a 4-panel rotation.

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Summarizing Paneling

Possible to have 3-, 4-, 7-, 9-, and 11 year cycles by connecting nodes with triangles

5,10 year cycles possible with parallelograms

A sub-paneling system is also used.

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FIA Ground Data Collection(“base program”, P2)

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FHM (P3, enhanced FIA)

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Summary of the sample design

Use auxiliary data (TM, photos,DEM…) for post-stratification of ground data.

Extensive use of FHM framework Provides National consistency Allows substantial flexibility for

regional issues through temporal and spatial intensification.

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Part II. Beyond the Base

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Marginal, Mean, and Inaccessible lands

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Case Study I: Alaska

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Reality Check

656,425 square miles =421 million acres = 70,000 FIA plots.

Alaska has 1 mile of road for every 42 square mile (1-to-1 in lower 48)

70 helicopter crews working 90 days for 10 years

N.D. 1 crew,1 Winnebago, 90 days

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Testing LIDAR and IFSAR

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Case Study II: Nevada

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Aerial photographs and digitizationAerial photographs and digitization

90 forest and woodland plots (3 photos per plot)

Scan at 12u

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Summary

FIA has been transformed from a group of regional inventories into a national program.

FIA data are have a multitude of applications

FIA is experimenting with a number of new technologies of expand and improve our products