STAND DESCRIPTION

Plot Name: Reference Stand 25 (Middle Santiam Research Natural Area)
Plot Size: 1.13 ha
Established: 1977
Remeasurements: 1984, 1989, 1995
Site Description
Latitude: 44.51
Longitude: 122.26
Elevation: 475 m
Aspect: -
Slope: level
Landform: stream terrace
Soil Parent Material: recent alluvium
Soil: Has not been classified.
Plant Association: Tsuga heterophylla/Polystichum munitum- Oxalis oregana
Age Class: Old-growth

Soils:

Soils are deep with large boulders and high gravel content increasing with depth.

General Stand Description:

This is an old-growth stand dominated by 350-380 year- old trees. Vegetation description is taken from tree stem- mapping data, as well as information on the understory collected on 4 reconnaissance plots located within the stand.
The overstory tree layer is composed almost solely of two species, the dominant layer of Pseudotsuga menziesii forming a relatively dense canopy while Tsuga heterophylla is emergent and forms secondary tree canopy with several trees in each size class. Thuja plicata and Acer macrophyllum are common but low in density. Alnus rubra occurs is border areas near the river and adjacent to the back channels behind the terrace where annual disturbance levels are the greatest.
The shrub layer is poorly developed with low coverage by Cornus nuttallii and Acer circinatum. Rhododendron macrophyllum occurs in trace amounts but is abundant on the footslopes adjacent to the terrace. Low shrubs are also scarce with the most abundant being Berberis nervosa.
The herb layer is very well developed with the characeristic high cover by Polystichum munitum and Oxalis oregana. Vancouveria hexandra, Coptis laciniata, Gymnocarpium dryopteris, Tiarella unifoliata, and Viola sempervirens are also abundant in this reference stand.
Stand Sructure and Composition
Live Tree Data at Last Measurement
Coarse Woody Debris: not available
Ecosystem and Population Dynamics (measurements for most recent interval, 1989-1995)
Net Bole Production: 2.2 Mg/ha/yr
Annual Mortality: 34.4 Mg/ha/yr
Percent of Trees Dying: total-2.3%/yr (53.8% were uprooted)