Southwest Tanana Susitna & Copper River Porcupine & Upper Yukon Coastal Middle & Lower Yukon F F OREST I I NVENTORY & A A NALYSIS INTERIOR ALASKA INVENTORY Full intensity grid (1 plot per 6,000 acres = 56500). Used in coastal AK and lower 48 states. Only forested plots (a subsample of all possible plots shown=23600) are inventoried. Issue: What is the inventory sampling design that will allow us to estimate the status and trends of the forest resources in interior Alaska in a cost effective, accurate, unbiased, and reasonably current fashion? Yukon River Tanana River none (not forested)North Slope (annual) & & 1973 Last InventoryArea (Interior shaded)

Sampling design Based on the standard intensity grid (1 plot per 6,000 acres) in productive forestland areas (the river corridors), with ¼ intensity (1 plot per 24,000 acres) in large areas of non-productive forestland. Remotely sensed images would be used to stratify the sample. LIDAR sampling of some productive and nonproductive plots. All forested plots within each of the 5 interior areas would be visited over a 4-year period (periodic design) rather than visiting a sub-sample of all plots across the entire 326,000,000 acres each year (annual design). Cycle length and remeasurement interval would be 20 years (vs standard 10 years). National core field plot design and data collection protocols. ESTIMATED ANNUAL COST: $2,073,000. This design would inventory approximately 16 million acres per year and allow completion of the statewide inventory every 20 years. The cost for non-productive and productive forestland is low ($0.12/acre). Areas of rapid change or natural disturbance can be sampled relatively quickly within the cycle. Statewide averages would be a mixture of old estimates and new data for many years. Trends would not be available for statewide changes, but would be based on periodic re- measurements of sections of the state. Full intensity grid (1 plot per 6000 acres) in productive areas – river corridors. 1/4 intensity (1 plot per 24,000 acres) in non-productive areas. Only forested plots (a subsample of all possible plots shown) are inventoried. Periodic Inventory - 20-year cycle Tanana River Yukon River

Tentative implementation schedule Southwest Tanana Susitna & Copper River Porcupine & Upper Yukon Coastal Middle & Lower Yukon noneNorth Slope 2004 (annual) Inventory dateArea (Interior shaded) Implementation depends on: - Client interest - Amount of resource - Change in resource - Logistic concerns Matanuska/Susitna Valley and Copper River regions are planned for initiation of interior inventory. The determining factors are: Proximity to Anchorage – gives data collection team opportunity to fine tune the system while close to home. Susitna Valley is a significant forest resource in terms of quantity and proximity to users Both Susitna Valley and Copper River regions contain forests that changed dramatically over recent years.

background 30 years since last set of inventories in Interior Alaska Inventory provides both current status as well as trends over time Trend can be determined with rolling average (with annual inventory) or with periodic comparisons (with periodic inventory). Error estimates and reliability of data are different for each. Although FIA is a nationally consistent program, it is recognized that Alaska, Puerto Rico, and the Pacific Islands are different: –Different sampling design –Different cycle length However, will follow national standards for: –Plot design –Compilation methods –Reporting