STAND DESCRIPTION
- Plot Name: Reference Stand 32 (HJA)
- Plot Size: 0.25 ha
- Established: 1978
- Remeasurements: 1983, 1988, 1994
- Site Description
- Latitude: 44.24
- Longitude: 122.19
- Elevation: 650 m
- Aspect: S-SW
- Slope: gentle to steep
- Landform: gentle concave sideslope and convex steep sideslope
separated by a subridge
- Soil Parent Material: colluvium and residuum from altered
volcanoclastic rocks (Little Butte Formation)
- Soil(s): shallow on ridge and 1-2 m deep on bench and
sideslopes
- Plant Association: Tsuga heterophylla/Rhododendron
macrophyllum/Berberis nervosa
- Age Class: largely second-growth
Soils:
No detailed soil profile descriptions are available at
the present time.
General Stand Description:
The tree layer is composed of a primary layer of dense
even-aged second-growth (about 145 years-old) Pseudotsuga
menziesii with only a few scattered old-growth trees of the
same species. The secondary tree layer is composed of
multiple age- and size-classes of Tsuga heterophylla and
Thuja plicata. The climax tree species of the area is Tsuga
heterophylla with Thuja plicata probably a co-climax species
of less importance.
The tall shrub layer is dominated by dense patches of
Rhododendron macrophyllum and more scattered stems of Acer
circinatum. Berberis nervosa and Gaultheria shallon are
dominants of the low shrubs and have very dense cover.
Typical of second-growth stands, Cornus nuttallii,
Castanopsis chrysophylla, Acer circinatum, and Gaultheria
shallon each are more important than they would be in typical
climax stands.
The herb layer is well developed and dominated by
Linnaea borealis and Chimaphila umbellata. Xerophyllum
tenax, Coptis laciniata, Viola sempervirens, and Polystichum
munitum are also abundant. Most of the Xerophyllum is
restricted to the subridge portion of the stand where soils
tend to be shallow and stony.
- Stand Structure and Composition
- Live Tree Data at Last Measurement (1994)
- Basal Area: 71.8 m2/ha
- PSME-44.9 m2/ha
- TSHE-13.6 m2/ha
- THPL-12.8 m2/ha
- Stem Numbers: 732/ha
- THPL-244/ha
- TSHE-228/ha
- PSME-208/ha
- Diameter Distribution:
- median-28.7 cm.
- quadratic mean-35.3 cm.
- max.-93.0 cm.
- Age: not available
- Height: not available
- Volume: 879.9 m3/ha
- PSME-588.6 m3/ha
- TSHE-170.8 m3/ha
- THPL-118.5 m3/ha
- Biomass: 459.0 Mg/ha
- PSME-336.8 Mg/ha
- TSHE-80.7 Mg/ha
- THPL-40.4 Mg/ha
- Coarse Woody Debris: no data available
- Ecosystem and Population Dynamics (measurements for most recent
interval, 1988-1994)
- Net Bole Production: 5.8 Mg/ha/yr
- Annual Mortality: 5.2 Mg/ha/yr
- Percent of Trees Dying: total-1.6%/yr