Agenda - Environmental Policy Board - 07/19/2021

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Title 190-Forestry Inventory Methods Technical Note Figure 3: View of Tree Through Wedge Prism IN' OUT Figure 4: View of Tree Through Angle Gauge I G IN OLJT • Establishing the Plot o At plot center, pivot in one direction, making a complete circle. Where to start the pivot is optional; some choose a cardinal direction, others simply the nearest tree. Use the wedge prism or angle gauge to identify trees that are in the plot. Inventory data will only be collected on the trees that are in the plot. o Note that each region will have a size threshold where trees below a certain diameter will not be included in a point sample; these trees will be sampled in regeneration plots. Consult with a forester on the lower size limit for point sampling. o If a tree is growing at an angle, tilt the prism or gauge to match. If the tree is obscured from view at DBH, either step away from plot center, maintaining the same distance to the tree in question, or target the tree above the obstruction. All trees counted in should be tallied by species and DBH within a 2-inch diameter class, at a minimum. Mark the plot center for reference if you need to physically measure the tree diameters; the eye quickly becomes calibrated and accurate ocular estimates of tree diameter can be achieved, but check your eye with actual measurements periodically. o Borderline trees are on the edge of the plot where it is difficult to determine whether they are in (fig. 5). The simplest approach is to count every other borderline tree as in; this approach provides an estimate of stand characteristics that is sufficient for most planning applications. If greater accuracy is desired, measure the distance from plot center to the borderline tree as per methods in appendix J of the FSVeg Common Stand Exam User Guide, Version: 2.12.6. (USDA -Forest Service 2015). (Technical Note No. 190-FOR-01, Jul 2018) 7