STAND DESCRIPTION

Plot Name: Reference Stand 30 (HJA)
Plot Size: 1 ha
Established: 1978
Remeasurements: 1983, 1988, 1995
Site Description
Latitude: 44.23
Longitude: 122.14
Elevation: 870 m
Aspect: N
Slope: 25%
Landform: large, moderately sloping bench
Soil Parent Material: colluvial andesite and volcanic ash
Soil: Deep, stony, and well drained
Plant Association: Tsuga heterophylla-Abies amabilis/Linnaea borealis
Age Class: Old-growth

Soils:

No description currently available.

General Stand Description:

RS 30 is an old-growth representative of the twinflower community as it occurs on north aspects in the middle of the transition zone which provides a very mesic environment. It is located adjacent to the Lookout Mountain trail just upslope from RS 29 and within a 10-minute hike from the trailhead at the end of the Mack Creek road.
The tree canopy is composed of the dominant large Pseudotsuga menziesii and scattered old-growth Thuja plicata. Tsuga heterophylla and Thuja plicata are the co-climax tree species on the site and occur in large numbers in smaller size classes. Abies amabilis is also present but in far fewer numbers than either Tsuga or Thuja.
The shrub layer of RS 30 is very well developed. Along with large amounts of understory tree regeneration, the small tree, Taxus brevifolia and tall shrubs Acer circinatum, Rhododendron macrophyllum, and Vaccinium parvifolium contribute to a dense shrub layer. Low shrubs are represented well in both diversity and density with Berberis nervosa dominant.
The herb layer is well developed, with nearly 70% total cover. Cornus canadensis, Linnaea borealis, and Chimaphila umbellata are dominant, but Tiarella unifoliata, Viola sempervirens, and Achlys triphylla are also abundant.
Stand Structure and Composition
Live Tree Data at Last Measurement (1995)
Coarse Woody Debris: No data available
Ecosystem and Population Dynamics (measurements for most recent interval, 1988-1995)
Net Bole Production: 4.4 Mg/ha/yr
Annual Mortality: 8.4 Mg/ha/yr
Percent of Trees Dying: total-0.5%/yr