Cool Fringe Mixed Hardwood Forest

Description

The Reference State 1.0 is a representative of the natural range of variability under pristine conditions. The reference state is a mixed forest consisting of hardwood species such as quaking aspen and paper birch with a strong native under story and minimal composition of conifer species (less than 5 percent). Predominant shrubs may include beaked hazelnut, shiny spirea, service berry, and Oregon grape. Other common species may include Western serviceberry, Oregon grape, wild honeysuckle, chokecherry, pink shinleaf, prickly rose, red raspberry, wild spirea, and white coralberry. Frequent herbaceous species found in the understory include baneberry, wild sarsaparilla, Lindley’s aster, wild strawberry, sweet-scented bedstraw, cream peavine, wild lily-of-the-valley, sweetroot, bracken fern, Maryland sanicle, starry false Solomon’s seal, purple meadowrue, Canada violet, and rough-leaved ricegrass. (Hoffman and Alexander 1987; Shepperd and Battaglia, 2002).

This site has three general community phases: advanced succession community phase, mid-succession community phase, and post disturbance community phase. State dynamics are maintained by interactions between climatic patterns and disturbance regimes. The ability of these hardwoods to clone themselves, and rhizomatous nature of aspen assist in their perseverance on the landscape. Negative feedback enhances ecosystem resilience and contribute to the stability of the state. These include the presence of all structural and functional groups, fuel loads, and retention of organic matter and nutrients.

Plant community phase changes are primarily driven by fire, periodic drought /or insect or disease, and extreme weather everts such as straight-line wind events or tornados. Periodic wildfires prevent over-mature aspen stands and maintain a naturally stratified mosaic of even-aged aspen stands in various stages of successional development. Many aspen stands are even-aged because of the rapid reproduction by suckering after a major disturbance. In the absence disturbance events, aspen stands become uneven-aged. Uneven-aged stands form under stable conditions where the overstory gradually disintegrates with disease or age and is replaced by suckers. Uneven-aged stands also occur where individual clones gradually expand into adjacent grasslands or shrublands.

Submodel

Description

The Timber managed and Invaded Herbaceous Sod State is largely the result of historic early European-American settlement of the Black Hills region. Fire suppression was common throughout recent history removing on of the primary ecological drivers of this system. This led to the decrease of this ecological site as it transitioned into conifer. Along with fire suppression these areas were often heavily grazed to supply beef and mutton for mining and logging communities. In later years these sites were often seeded to introduced grasses and clover to increase forage quality or farmed for grain crop production. In many cases the shift in land use from forest to livestock, forage, and crop production remains. Those areas that are not under intensive management resist transitioning back to a forest plant community, even though the soils still exhibit forest attributes. The dominant plants associated with this state are introduced sod-forming grasses, introduced legumes, and weedy forbs. This state is very resistant to change through management alone.

Submodel