Changes in forest resources have been estimated in a variety of ways. This paper focuses on extensive forest surveys rather than on sentinel‐site investigations. The sampling design and plot design used are key to precise estimates of change. Alternative sampling designs include temporary surveys, Continuous Forest Inventory, and Sampling with Partial Replacement. Each can be used in conjunction with stratified sampling or double sampling for stratification. Plot designs can involve variable‐radius or Bitterlich sampling for trees, and fixed‐area plots for most attributes. In extensive surveys, it is efficient to group plots into clusters. Plots must be sampled at a frequency that is commensurate with the rate of change, degree of interest, and funding available. Often, plots are less than a hectare in size and spaced widely across the population. Continuous Forest Inventory, with or without stratification, is efficient for estimating current values, net change, and components of change. Much work remains in scaling to understand landscape‐level interactions and to identify stressors and indicators of forest health and sustainability.

The establishment of several large area monitoring networks over the past few decades has led to increased research into ways to spatially balance sample locations across the landscape. Many of these methods are well documented and have been used in the past with great success. In this paper, we present a method using geographic information systems (GIS) and fractals to create a sampling frame, superimpose a tessellation and draw a sample. We present a case study that illustrates the technique and compares results to those from other methods using data from Voyageurs National Park in Minnesota. Our method compares favorably with results from a popular plot selection method, Generalized Random Tessellation Stratified Design, and offers several additional advantages, including ease of implementation, intuitive appeal, and the ability to maintain spatial balance by adding new plots in the event of an inaccessible plot encountered in the field.

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