State 1
Reference

Community 1.1
Douglas-fir, Pacific Madrone, Oceanspray, and Rattlesnake Plantain

Structure is multistory with small gap dynamics. Douglas-fir is the dominant tree species in the historic climax plant community. Pacific madrone will establish itself as a minor component in some instances but may occasionally be major component. As Douglas-fir ages it can withstand more serious fire intensities; additionally, following fire or other stresses, trees generally produce copious amounts of seed. This situation would allow the site to develop into one that contains several age classes of Douglas-fir. Pacific madrone, a thin barked species, will be top-killed by fire but can sprout prolifically from underground burls, provided it receives adequate sunlight. Madrone also favors mineral soil for seedling establishment, competing with coniferous seedlings. If Douglas-fir does not re-occupy the site quickly, Pacific madrone will take advantage of the disturbed mineral soil and become a major component of the community, as will oceanspray. If a seed source is present, lodgepole pine will also become established on these sites.

Forest overstory. Dominated by Douglas-fir with varying amounts of madrone (0 to 20percent); lodgepole pine may be present (up to 30 percent on some locations); grand fir and western redcedar present in small numbers (less than 5 percent)

Forest understory. Shrub species dominate.

Community 1.2
Douglas-fir, Oceanspray, and Salal

Structure: Mosaic of mature overstory and regenerating openings This community retains some areas that resemble community 1.1 but also contains moderate sized (2 to 5 acres) areas of regeneration. Moderate to intense fires, pockets of disease, or uneven-aged management (group selection or shelterwood with reserves) can create this plant community. Depending on the seed sources that are present, patches of seedling and sapling may contain Douglas-fir, madrone, Oregon white oak, and/or lodgepole pine as well as oceanspray, dwarf rose and Cascade barberry (Mahonia nervosa, known locally as Oregongrape). Both harvesting and fire can spur the growth of pioneering species. Lodgepole pine can out-compete Douglas-fir in height growth early, but a mixed species stand results if the seedling density isn’t too high. In the absence of further management, some patches may be dominated by shrub species until their coverage gradually diminishes due to shading by the overstory, which can take many years.

Community 1.3
Oceanspray, Salal, Douglas-fir, Lodgepole Pine, and Madrone

Structure is single story shrub. Community 1.3 consists of forestland in regeneration. Species composition depends on the natural seed sources present and the intensity of management. If the regeneration is planted, Douglas-fir is most likely be selected. Douglas-fir, lodgepole pine, Pacific madrone and Oregon white oak are the common tree species available for natural seeding while typical shrubs include oceanspray, trailing blackberry, dwarf rose and Cascade barberry (Mahonia nervosa, known locally as dull Oregongrape).

Community 1.4
Douglas-fir and Lodgepole Pine

Structure is single story with diminished understory This community typically consists of the "stem exclusion" phase of stand development. The overstory canopy is closed, leading to intense competition for sunlight and a diminished understory. These stands are typically very dense and have minimal vertical differentiation.

Community 1.5
Douglas-fir, Lodgepole Pine, Madrone, Oceanspray, Salal, and Rattlesnake Plantain

Structure is single story with scattered openings This community consists of maturing forest. Although still basically single-story in appearance, the stand is starting to differentiate vertically. Some sunlight reaches the forest floor, allowing for an increased understory of mainly shrub species.

Pathway 1.1A
Community 1.1 to 1.2

This pathway represents a larger disturbance with moderate to high intensity fires or major wind storms would be the natural disruptive forces while a group selection or shelterwood (with reserves) harvest would represent the human-initiated community. Areas of regeneration would generally range from 2 to 5 acres in size.

Pathway 1.1B
Community 1.1 to 1.3

This is the pathway of a major disturbance, such as a stand-replacing fire or clear-cut, followed by prescribed fire, with the intention of regeneration.

Pathway 1.2A
Community 1.2 to 1.1

This pathway indicates growth over time with no additional disturbances. The areas of regeneration pass through the typical stand phases, competitive exclusion, maturation, understory re-initiation, until they resemble the old-growth structure of the community 1.1.

Pathway 1.2B
Community 1.2 to 1.3

This pathway represents intensive management, such as a change from uneven-aged management to even-aged management. Block harvest with a post-harvest burn leads to a plant community in the stand initiation stage. Site preparation and planting improved seedlings lead to a single-species stand. No further management leads to a mixed species stand that is dependent on natural seed sources.

Pathway 1.3B
Community 1.3 to 1.4

This pathway represents absence of management and denotes only growth over time. Without active management, large areas can be dominated by various shrubs until they are gradually shaded out by the overstory, which can take many years.

Pathway 1.3A
Community 1.3 to 1.5

This pathway represents growth over time in conjunction with active management. Precommercial thinning, commercial thinning, or both, combined with understory control, lower the stand density and decrease competition between trees.

Pathway 1.4A
Community 1.4 to 1.5

This pathway represents growth over time, with or without thinning. If an area is not thinned, mortality occurs in the intermediate and suppressed trees.

Pathway 1.5A
Community 1.5 to 1.1

This pathway represents no further management. Growth over time leads to continued vertical differentiation, including scattered pockets of reproduction and an increase in the number of shrubs and forbs.

Pathway 1.5B
Community 1.5 to 1.3

This pathway represents intensive management focused on wood products. Clear-cutting, prescribed fire, or other site preparation and tree planting are the management steps.

State 2
Converted

Community 2.1
Managed Cropland or Hayland

Structure is annual or perennial non-native species monoculture. This community consists of a range of crops, including annually planted species, short-lived perennial species, and more permanent shrubby crops. Hay and grasses and legumes for silage are included in this community.

Community 2.2
Introduced Grass and Shrub

Structure is annual or perennial herbaceous or shrubby species. Community 3.2 is characterized by low-level or more intermittent management activity such as occasional or light grazing or sporadic mowing. This plant community is dominated by introduced weedy species and the less frequent disturbance supports a more shrubby character. The site is grazed, mowed or burned often enough to prevent re-establishment of forest. Dominant shrubs are typically invasive rhizomatous species that form thickets such as Himalayan blackberry (Rubus armeniacus) or those that develop a robust seedbank and flourish in open conditions such as Scotch broom (Cytisus scoparius). Some tougher native shrub species such as California blackberry (Rubus ursinus) may be interspersed. Wetter areas commonly support non-native rhizomatous grasses. Between shrub thickets introduced pasture species such as tall fescue (Schedonorus arundinaceus), orchardgrass (Dactylis glomerata) and red fescue (Festuca rubra) are common. Fire and soil disturbing activities often favors an increase in western brackenfern (Pteridium aquilinum).

Community 2.3
Managed Perennial Grassland

This community is an introduced grassland that receives regular grazing or mowing disturbance and may include soil amendments such as fertilizers or lime. Weeds are aggressively controlled and desired herbaceous species are reseeded as necessary. Grazing, mowing and other weed control actions prevent the phase from transitioning to a forested state. This plant community is typically dominated by introduced perennial pasture species that are seeded after clearing. Common species include tall fescue (Schedonorus arundinaceus), orchardgrass (Dactylis glomerata) and red fescue (Festuca rubra).

Pathway 2.1A
Community 2.1 to 2.2

This pathway occurs by a reduction in frequent agronomic management disturbance (e.g. discontinued seedbed preparation, harvesting, mowing, etc.) which provides opportunity for grasses, forbs, shrub and bramble-forming species to establish. Intermittent disturbances, such as periodic grazing, targeted mowing or prescribed fire may maintain this community, preventing it from advancing to a forested state.

Context dependence. This pathway occurs by a reduction in frequent agronomic management disturbance (e.g. discontinued seedbed preparation, harvesting, mowing, etc.) which provides opportunity for grasses, forbs, shrub and bramble-forming species to establish. Intermittent disturbances, such as periodic grazing, targeted mowing or prescribed fire may maintain this community, preventing it from advancing to a forested state.

Pathway 2.1B
Community 2.1 to 2.3

This pathway occurs by intentional establishment of a perennial grass-dominated plant community. Often, the site will be prepped for seeding and desired pasture species artificially sown. In some cases, simply discontinuing crop production activities may allow the site to transition to grass, provided emergence of woody shrubs or trees is actively controlled with mowing, fire, or chemical treatment. Consistent grazing is essential to the maintenance of this community and to prevent development of woody shrubs. Other maintenance practices, such as targeted mowing, prescribed fire, chemical treatment, or other mechanical treatment are utilized as needed.

Pathway 2.2B
Community 2.2 to 2.1

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

Pathway 2.2A
Community 2.2 to 2.3

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

Pathway 2.3A
Community 2.3 to 2.1

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

Pathway 2.3B
Community 2.3 to 2.2

This pathway occurs by a reduction in grazing and associated management disturbance (e.g. discontinued seedbed preparation, harvesting, mowing, etc.) which provides opportunity for shrubs and bramble-forming species and other weedy, invasive species to establish. Intermittent disturbances, such as periodic grazing, targeted mowing or prescribed fire may maintain this community, preventing it from advancing to a forested state.

Transition T1A
State 1 to 2

This transition is caused by an intentional clearing of land or a stand replacing fire in state 1, followed by intense, frequent disturbance such as grazing, mowing, crop production, or frequent fire to prevent trees from re-establishing. This transition can be initiated from any community in state 1.

Transition T2A
State 2 to 1

This restoration occurs by artificial or natural re-establishment over time of species resembling overstory and understory diversity typical of the reference state. Intentional planting, site preparation, and control of competing invasive weeds will accelerate this transition. This transition can be initiated from any community in state 2.