Name:
Thuja plicata / Gymnocarpium dryopteris Forest
Reference:
NatureServe Biotics 2019
Description:
This <i>Thuja plicata</i> forest association is known from the northern Rocky Mountains of British Columbia, northern Idaho and northwestern Montana. It represents one of the driest <i>Thuja plicata</i> riparian communities, and the driest <i>Thuja</i> type to have a fern layer. It occurs at elevations ranging from 975 to 1370 m (3200-4500 feet). Typical locations include slopes or benches along major mountain streams. Slopes are moderate to steep, and stands are generally located on mid to lower slopes. Parent materials are usually quartzite, sandstone, or schist, often mixed or overlain with volcanic ash. Soils are gravelly loams to silty clay loam to silt. Stands are subirrigated yet well-drained. Duff layers average 8 cm in depth. Late-seral stands have closed canopies and are dominated by <i>Thuja plicata</i>. Stands not in a late-seral stage are more heterogeneous, with a mix of conifers in addition to <i>Thuja</i>. Seral species persisting in these stands include <i>Abies grandis</i> as the most abundant and common. Others include <i>Tsuga heterophylla, Picea engelmannii</i> (or <i>Picea x albertiana</i>), <i>Pinus monticola, Larix occidentalis</i>, and <i>Pseudotsuga menziesii</i>. The shrub layer is typically limited to 10-20% total cover. Highly constant species include <i>Acer glabrum, Lonicera utahensis, Linnaea borealis, Rubus parviflorus</i>, and <i>Taxus brevifolia</i>. The herbaceous layer has mostly ferns and forb species with few to no grasses. <i>Gymnocarpium dryopteris</i> is diagnostic for this type, with at least 1% cover, but is often much more abundant. <i>Athyrium filix-femina</i> or <i>Adiantum pedatum</i> are often present, but with low cover or only on moist microsites. Other highly constant mesic forbs include <i>Clintonia uniflora, Tiarella trifoliata, Coptis occidentalis, Osmorhiza berteroi, Prosartes hookeri, Aralia nudicaulis</i>, and <i>Maianthemum stellatum</i>.
Accession Code:
urn:lsid:vegbank.org:commConcept:29385-{CAFDFC11-26B0-4B1F-8C50-66C80750A7E2}
Plot-observations of this Community Concept:
1
|
