Accuracy and suitability of selected sampling methods within conifer dominated riparian zones

Sixteen sampling alternatives were examined for their performance to quantify selected attributes of overstory conifers in riparian areas of western Oregon. Each alternative was examined at eight headwater forest locations based on a 0.52 ha square stem maps. The alternatives were evaluated for selected stand attributes (trees per hectare, basal area per hectare and height to diameter ratio), using root mean square error, absolute percent bias, and mean absolute deviation as criteria. In general, rectangular strip designs outperformed fixed area circular or radial plots and variable area plots. Sampling 3.6 m wide strips perpendicular to the stream outperformed all other alternatives.