State 1
Reference

Community 1.1
Western Hemlock, Red Alder, and American Skunkcabbage

Western hemlock-red alder /American skunkcabbage

Structure: Mosaic of mature overstory and regenerating openings

The reference community represents a lack of major disturbance from windthrow or ponding for at least 80 years, which allows the pioneering species to form a mature canopy. Western hemlock and red alder are the dominant overstory species. Western redcedar and Douglas-fir may be present, but they are limited to drier microsites such as nurse logs and mounds. Shrubs commonly are restricted to nurse logs, stumps, and higher microsites. Understory species include salal, American skunkcabbage, evergreen huckleberry, California wax myrtle (Morella californica), swordfern (Polystichum munitum), deer fern (Blechnum spicant), and sedges (Carex spp.). Common disturbances include small gap dynamics (1/2-acre openings or smaller) following windstorms and excessive ponding.

Community 1.2
Red Alder, American Skunkcabbage, and Sedge

Red alder/American skunkcabbage/sedge

Structure: Forb and sedge establishment

Community phase 1.2 represents a forest that is undergoing regeneration or stand initiation immediately following excessive ponding or windthrow. Scattered remnant mature trees and shrubs may be in some areas, and woody debris is abundant. Loss of the overstory and the fallen trees may impact the hydrology by resulting in more frequent, longer periods of ponding. Successful regeneration is dependent on the local seed source, an adequate seedbed, and sufficient light (Nierenberg, 2000). Rapid recolonization is limited to plants that are well adapted to saturated soil conditions much of the year. American skunkcabbage and sedges will begin to re-establish during this phase.

Community 1.3
Red Alder, Western Hemlock, American Skunkcabbage, and Sedge

Red alder-western hemlock/American skunkcabbage/sedge

Structure: Single story with dense understory

Community phase 1.3 is an early seral forest in regeneration. Scattered remnant mature trees may be present. Red alder is the primary tree and will establish quickly with an open canopy. Western hemlock will regenerate on hummocks and mounds and will begin to establish a canopy. Shrubs are sparse, but species such as salal and evergreen huckleberry become established on fallen trees and in higher microsites. Understory species may include deer fern, American skunkcabbage, and sedges.

Pathway 1.1A
Community 1.1 to 1.2

This pathway represents excessive ponding that results in a shallow rooting zone. The trees are susceptible to windthrow, which may create pockets of fallen trees larger than 1 acre in size. Catastrophic windstorms may be stand replacing.

Pathway 1.2A
Community 1.2 to 1.3

This pathway represents growth over time with no further major disturbance.

Pathway 1.3B
Community 1.3 to 1.1

This pathway represents no further major disturbance. Continued growth over time and ongoing mortality lead to increased vertical diversification. The community begins to resemble the structure of the reference community, including small pockets of regeneration (both deciduous and coniferous) and a more diversified understory.

Pathway 1.3A
Community 1.3 to 1.2

This pathway represents excessive ponding that results in a shallow rooting zone. The trees are susceptible to windthrow, which may create pockets of fallen trees larger than 1 acre in size. Catastrophic windstorms may be stand replacing.

State 2
Converted

Community 2.1
Managed Cropland or Hayland

Managed Cropland or Hayland

Structure: Annual or perennial non-native species monoculture

Community phase 2.1 may consist of a range of crops, including annually planted species, short-lived perennial species, and more permanent shrubby plants. Hay and grasses and legumes for silage are included in this community phase.

Community 2.2
Non-Native Grassland and Shrubland

Non-native Grassland and Shrubland

Structure: Annual or perennial herbaceous or shrubby species

Community phase 2.2 is characterized by low-level agronomic or management activity such as adding soil nutrients, intensive grazing management, regular mowing, or weed control. This plant community commonly consists dominantly of introduced weedy species. Areas that have extremely low fertility or are subject to heavy grazing pressure have a higher proportion of annual, stoloniferous, or rhizomatous species. Wetland areas commonly support dominantly non-native rhizomatous grasses. The plant community may include remnants of introduced pasture species that commonly are seeded.

Community 2.3
Managed Grassland

Managed Grassland

Structure: Perennial herbaceous species

Community phase 2.3 receives regular agronomic inputs, including adding soil nutrients and other soil amendments such as lime, implementing grazing management plans, regular mowing, controlling weeds, and reseeding as needed. This plant community typically includes introduced perennial pasture and hay species that commonly are seeded. In areas of historic native grassland, mixtures of perennial and annual native species may be seeded and managed by appropriate agronomic and livestock management activities. Minor amounts of introduced species that commonly are in non-native grassland and shrubland communities (community phase 2.2) are in this phase.

Pathway 2.1A
Community 2.1 to 2.2

In the absence of agronomic and livestock management activities, seeds from surrounding weedy plant communities will be transported to the site by wind, animals, or vehicle traffic. Adapted species will become established. Management activities include tilling, adding soil nutrients and other soil amendments such as lime, mowing, burning, harvesting or chemically controlling vegetation, planting to desirable herbaceous species, and implementing grazing management plans.

Pathway 2.1B
Community 2.1 to 2.3

This pathway represents agronomic and livestock management activities, including tilling, adding soil nutrients and other soil amendments such as lime, mowing, burning, harvesting or chemically controlling vegetation, planting to desirable herbaceous species, and implementing grazing management plans.

Pathway 2.2B
Community 2.2 to 2.1

This pathway represents agronomic activities such as tilling, adding soil nutrients and other soil amendments such as lime, mowing, burning, harvesting or chemically controlling vegetation, and planting to desirable crop species.

Pathway 2.2A
Community 2.2 to 2.3

This pathway represents agronomic and livestock management activities, including tilling, adding soil nutrients and other soil amendments such as lime, mowing, burning, harvesting or chemically controlling vegetation, planting to desirable herbaceous species, and implementing grazing management plans.

Pathway 2.3A
Community 2.3 to 2.1

This pathway represents agronomic activities, including tilling, adding soil nutrients and other soil amendments such as lime, mowing, burning, harvesting or chemically controlling vegetation, and planting to desirable crop species.

Pathway 2.2B
Community 2.3 to 2.2

In the absence of agronomic and livestock management activities, seeds from surrounding weedy plant communities will be transported to the area by wind, floodwater, animals, or vehicle traffic. Adapted species will become established. Management activities include tilling, adding soil nutrients and other soil amendments such as lime, mowing, burning, harvesting or chemically controlling vegetation, planting to desirable herbaceous species, and implementing grazing management plans.

Transition T1A
State 1 to 2

This pathway represents a change in land use. Land management includes modifications to the hydrologic function to develop pasture and agriculture. Non-native seed disbursement is introduced (intentionally or unintentionally), which alters the reference community.

Transition T2A
State 2 to 1

This pathway represents restoration of the natural hydrologic function and native plant habitat. Native seed sources and extensive management and mitigation of brush and invasive species are needed to restore the community.