The WFDP is located near Carson, WA in the Research Natural Area of the Gifford Pinchot National Forest, with the plot center at 45.82° N, 121.95° W. Elevation ranges from 352.4 m to 384.7 m for a vertical relief of 32.3 m (Fig. 1).

Figure 1. Topography of the Wind River Forest Dynamics Plot. The 20 m grid is shown on a LiDAR-derived digital elevation model of the plot (1 m horizontal resolution). The maximum elevation within the plot is 384.7 m; the minimum elevation is 352.4 m (5 m contours shown). LiDAR-derived bare-earth model courtesy of Watershed Sciences, Corvallis, Oregon.

Figure 2. Orthophoto of the Wind River Forest Dynamics Plot. This 15 cm resolution orthophoto matches the spatial extent of the topography in Fig. 1 (5 m contours superimposed). Orthophoto courtesy of Watershed Sciences, Corvallis, Oregon. The NEON tower is visible in the upper right corner of the image.

Figure 3. Temperature and precipitation in the Wind River Forest Dynamics plot (top) from PRISM 800 m climate normals (1981-2010), the water balance (middle) using a Thornthwaite-type evapotranspiration model, and historical trends based on PRISM 4 km monthly climate data.

Figure 4. Every live woody stem ≥1 cm diameter at breast height (DBH, 1.37 m) was tagged in 2010 and 2011 (30,973 live trees and 1,966 snags). The WFDP was expanded to 27.2 ha in 2016 (at the first remeasurement) to more fuly include the moisture gradent at the site. Mortality and recruitment surveys are conducted annually, factors associated with death are identified for all newly dead trees. Diameter is remeasured every 5 years.

Dendrometer bands

Figure 5. The 326 manual dendrometer bands were installed in 2013, and 43 automated logging dendrometers were installed in 2014 (41 TreeHuggers and two DBL60 from ICT International). These bands are remeasured periodically throughout the growing season to monitor tree growth and timing of water availability.

Temperature sensors and seedling study

Figure 6. Locations of 63 seedling subplots. Each subplot contains a 0.3 m² seed trap to measure dispersal and a 1 m² quadrat to measure seedling establishment and demography. Each subplot also contains a data logging temperature and light sensor (Onset HOBO logger).

LiDAR

Figure 7. High resolution LiDAR point cloud showing canopy heights in the WFDP. The boom of the old Canopy Crane can me seen in the northeast corner.

Coarse woody debris.

Figure 8. Location of all coarse woody debris from main stems ≥ 10 cm diameter at the large end.

Continous Shrub Cover.
Figure 9. Patches of continuous shrub cover mapped throughout the WFDP. The shrubs and downed wood are important factors in tree demography.