The AFIS tree growth model for updating annual forest inventories in Minnesota

Abstract

As the Forest Service moves towards annual inventories, states may use model predictions of growth to update unmeasured plots. A tree growth model (AFIS) based on the scaled Weibull function and using the average-adjusted model form is presented. Annual diameter growth for four species was modeled using undisturbed plots from Minnesota's Aspen-Birch and Northern Pine Inventory Units. On the validation database, the AFIS model showed increased precision over the recalibrated STEMS model by 5 percent for diameter predictions and 8 percent for stand basal area predictions. The average adjusted model form has a number of desirable features.

Parent Publication

• Integrated tools for natural resources inventories in the 21st century

Citation

Holdaway, Margaret R. 2000. The AFIS tree growth model for updating annual forest inventories in Minnesota. In: Hansen, Mark; Burk, Tom, eds. Integrated tools for natural resources inventories in the 21st century. Gen. Tech. Rep. NC-212. St. Paul, MN: U.S. Dept. of Agriculture, Forest Service, North Central Forest Experiment Station. 507-514.