Print Report
A4097 Pinus muricata - Pinus radiata Woodland Alliance
Type Concept Sentence: This alliance includes closed-cone pine stands dominated by endemic tree taxa Pinus contorta var. bolanderi, Pinus muricata, and/or Pinus torreyana that occur in scattered groves along the California and Baja California coasts. These forests and woodlands are limited to coastal areas with moderate maritime climate and likely receive more annual precipitation than nearby coastal chaparral, in part due to fog drip.
Common (Translated Scientific) Name: Bishop Pine - Monterey Pine Woodland Alliance
Colloquial Name: Californian Coastal Closed-Cone Pine Woodland
Hierarchy Level: Alliance
Type Concept: This alliance includes closed-cone pine stands dominated by endemic tree taxa Pinus contorta var. bolanderi, Pinus radiata, and/or Pinus muricata (on the Channel Islands). Pinus attenuata may be dominant or codominant in some occurrences. Stands may be pygmy woodland expressions where indurated subsoil underlies acidic sands (ancient marine terraces). Other associated plant species include Arctostaphylos hookeri, Arctostaphylos nummularia, Arctostaphylos tomentosa, Gaultheria shallon, Ledum groenlandicum, Morella californica, Quercus pacifica, Arctostaphylos tomentosa ssp. crustacea, Baccharis pilularis, Comarostaphylis diversifolia ssp. planifolia, Galium nuttallii ssp. insulare, Diplacus parviflorus, Rhododendron macrophyllum, and Vaccinium ovatum. The lichen and moss component of this alliance is very diverse, includes Cladonia spp., and can be abundant in these communities. This alliance occurs on the mainland in central and northern California, and on Santa Cruz and Santa Rosa islands, and Guadalupe Island (Baja California, Mexico). These forests and woodlands are limited to coastal areas with moderate maritime climate and likely receive more annual precipitation than nearby coastal chaparral, in part due to fog drip. They occur on marine sedimentary, non-metamorphosed features, often on podsols or on sterile sandstone on dry ridges, headlands, uplifted maritime terraces, rocky ridges, and sand dunes. They are found primarily on upper positions of slopes, though occasionally lower and in canyons, at predominately north-facing, cooler aspects. Soils in dry sites are shallow, acidic, and may be inadequately drained; soils on seasonally flooded sites are sterile with cemented hardpans. Elevation ranges from sea level to 450 m.
Diagnostic Characteristics: Typically localized stands of closed-cone pines along the California coast dominated by Pinus contorta var. bolanderi, Pinus radiata, and Pinus torreyana, or Pinus muricata. Associated shrubs and herbs will include those found in coastal areas of California (Arctostaphylos nummularia, Gaultheria shallon, Ledum groenlandicum, Morella californica, Rhododendron macrophyllum, and Vaccinium ovatum).
Rationale for Nominal Species or Physiognomic Features: No Data Available
Classification Comments: This alliance is based on the ecological system ~California Coastal Closed-Cone Conifer Forest and Woodland (CES206.922)$$. While this alliance includes several MCV alliances (Sawyer et al. 2009), they are put together into one alliance of the coastal cypress and pine stands in this treatment; they are separated from the Coast Ranges and Sierra Nevada foothills cypress or pine stands, where a less "coastal" floristic component will be found. While Pinus contorta var. contorta can be found in some associations of this alliance, Pinus contorta var. contorta associations are placed in ~Vancouverian Dry Coastal Beach Pine Forest & Woodland Group (G205)$$, or else in one of the swamp or bog/fen groups when found in swamp or fen settings.
Pinus radiata is one of the most widely cultivated trees in the world. However, there are only three natural occurrences of Pinus radiata known, all located near Monterey in coastal California. Populations of Pinus muricata have been taxonomically treated in several different ways. Cone persistence varies from stand to stand. All stands and populations of Pinus muricata are included in this alliance. Pinus torreyana stands have been pulled out and are now in their own alliance, ~Pinus torreyana Woodland Alliance (A4221)$$ (January 2016).
Unlike the other pine alliance occurring in the Channel Islands, Pinus muricata has a closer affinity to the north coast, as evidenced by the occurrence of Vaccinium ovatum and relict species of mosses - whose only occurrences south of Santa Cruz County are within bishop pine forests. The fossil record indicates that bishop pine once had a wider distribution. It is primarily found in northern and central California with smaller relict populations to the south, including the Channel Islands. Taxonomically, Pinus radiata and Pinus muricata have been placed in the same subsection, along with Pinus attenuata, whereas Pinus torreyana is treated separately.
Pinus radiata is one of the most widely cultivated trees in the world. However, there are only three natural occurrences of Pinus radiata known, all located near Monterey in coastal California. Populations of Pinus muricata have been taxonomically treated in several different ways. Cone persistence varies from stand to stand. All stands and populations of Pinus muricata are included in this alliance. Pinus torreyana stands have been pulled out and are now in their own alliance, ~Pinus torreyana Woodland Alliance (A4221)$$ (January 2016).
Unlike the other pine alliance occurring in the Channel Islands, Pinus muricata has a closer affinity to the north coast, as evidenced by the occurrence of Vaccinium ovatum and relict species of mosses - whose only occurrences south of Santa Cruz County are within bishop pine forests. The fossil record indicates that bishop pine once had a wider distribution. It is primarily found in northern and central California with smaller relict populations to the south, including the Channel Islands. Taxonomically, Pinus radiata and Pinus muricata have been placed in the same subsection, along with Pinus attenuata, whereas Pinus torreyana is treated separately.
Similar NVC Types: No Data Available
note: No Data Available
Physiognomy and Structure: This alliance has an intermittent to continuous tree canopy less than 30 m in height. The shrub and herbaceous layers are highly variable in cover, ranging from completely absent to abundant.
Floristics: Stands in this alliance are dominated by endemic tree taxa Pinus contorta var. bolanderi, Pinus radiata, and/or Pinus muricata. Pinus attenuata may be dominant or codominant in some occurrences. Other conifers that may be associated include Abies grandis, Arbutus menziesii, Hesperocyparis pigmaea (= Callitropsis pigmaea), Notholithocarpus densiflorus (= Lithocarpus densiflorus), Pinus contorta var. contorta, Pinus radiata, Pseudotsuga menziesii, Quercus agrifolia, Sequoia sempervirens, Tsuga heterophylla, and Umbellularia californica. Stands may be stunted "pygmy woodlands" where hardened subsoil underlies acidic sands (ancient marine terraces). On the mainland, associated shrub species may include Arctostaphylos hookeri, Arctostaphylos nummularia, Arctostaphylos tomentosa, Diplacus aurantiacus ssp. aurantiacus, Gaultheria shallon, Ledum groenlandicum, and Morella californica (= Myrica californica). On the Channel Islands, associated shrubs may include Arctostaphylos tomentosa ssp. crustacea (= Arctostaphylos crustacea), Baccharis pilularis (= ssp. consanguinea), Comarostaphylis diversifolia ssp. planifolia, Galium nuttallii ssp. insulare, Diplacus parviflorus (= Mimulus aurantiacus var. parviflorus), Quercus pacifica, Rhododendron macrophyllum, Rubus spp., Rhamnus spp., Symphoricarpos mollis, and Toxicodendron diversilobum. The lichen and moss component of this alliance is very diverse, includes Cladonia spp., and can be abundant in these communities. In the northern portion of the range Pinus muricata mixes with other conifers. These can include Pinus contorta var. contorta, Pinus contorta var. bolanderi, Pinus radiata, Pseudotsuga menziesii, Hesperocyparis pigmaea (= Cupressus goveniana ssp. pygmaea), and/or Sequoia sempervirens. Island stands are notably different in species composition compared to mainland stands. Species composition also varies from north to south, with northern stands rich in ericaceous species. Common forbs include Achillea millefolium, Carex globosa, and Hieracium argutum and ferns Polystichum munitum and Pteridium aquilinum.
Species of Interest: Arctostaphylos tomentosa ssp. insulicola (= Arctostaphylos crustacea ssp. insulicola) (CRPR 4.2) or Arctostaphylos tomentosa ssp. subcordata (= Arctostaphylos crustacea ssp. subcordata) (CRPR 4.2), Galium nuttallii ssp. insulare (CRPR 4.3), Diplacus parviflorus (CRPR 4.3), and Quercus pacifica (CRPR 4.2) are often found in this alliance and Lotus dendroideus var. dendroideus (= Acmispon dendroideus var. dendroideus) (CRPR 4.2), Arctostaphylos confertiflora (FE, CRPR 1B.2), Lilium humboldtii ssp. ocellatum (CRPR 4.2), Quercus parvula var. parvula (CRPR 4.2), Quercus tomentella (CRPR 4.2), and Sanicula hoffmannii (CRPR 4.3) are sometimes found. All of the following species tracked by the CNPS Rare Plant Inventory (2015) occur at less than 20% constancy in the samples of this alliance: Baccharis plummerae ssp. plummerae (CRPR 4.3), Castilleja lanata ssp. hololeuca (= Castilleja hololeuca) (CRPR 1B.2), Dendromecon harfordii (CRPR 3.2), Hazardia detonsa (CRPR 4.3), Heuchera maxima (CRPR 1B.2), Rhamnus pirifolia (CRPR 4.2), Ribes thacherianum (CRPR 1B.2), Salvia brandegeei (CRPR 1B.2), and Solanum clokeyi (CRPR 4.2).
Species of Interest: Arctostaphylos tomentosa ssp. insulicola (= Arctostaphylos crustacea ssp. insulicola) (CRPR 4.2) or Arctostaphylos tomentosa ssp. subcordata (= Arctostaphylos crustacea ssp. subcordata) (CRPR 4.2), Galium nuttallii ssp. insulare (CRPR 4.3), Diplacus parviflorus (CRPR 4.3), and Quercus pacifica (CRPR 4.2) are often found in this alliance and Lotus dendroideus var. dendroideus (= Acmispon dendroideus var. dendroideus) (CRPR 4.2), Arctostaphylos confertiflora (FE, CRPR 1B.2), Lilium humboldtii ssp. ocellatum (CRPR 4.2), Quercus parvula var. parvula (CRPR 4.2), Quercus tomentella (CRPR 4.2), and Sanicula hoffmannii (CRPR 4.3) are sometimes found. All of the following species tracked by the CNPS Rare Plant Inventory (2015) occur at less than 20% constancy in the samples of this alliance: Baccharis plummerae ssp. plummerae (CRPR 4.3), Castilleja lanata ssp. hololeuca (= Castilleja hololeuca) (CRPR 1B.2), Dendromecon harfordii (CRPR 3.2), Hazardia detonsa (CRPR 4.3), Heuchera maxima (CRPR 1B.2), Rhamnus pirifolia (CRPR 4.2), Ribes thacherianum (CRPR 1B.2), Salvia brandegeei (CRPR 1B.2), and Solanum clokeyi (CRPR 4.2).
Dynamics: This alliance only occurs within the zone of coastal fog incursion. It is also adapted to periodic fires. Stands of Pinus muricata are often even-aged as they originate after a fire, and the species'' cones are usually opened by fire. A fire-free period of 80 years or more would allow trees to succumb to age or disease without reproducing. Pitch canker, a fungal disease, has attacked many specimens of Pinus radiata. There appears to be some natural resistance, but fire suppression over the last hundred years has resulted in uniform stands lacking diversity in age and structure. These factors make stands of this alliance more susceptible to this disease. The Pinus muricata alliance occurs as disjunct localized stands; however, it ranges more widely and covers a wider array of ecological settings than other coastal closed-cone pine alliances. Conservation requires examples throughout the full range of environmental settings, and periodic fire is an important factor in maintaining these stands.
Pitch pine canker (Fusarium subglutinis f. sp. pini) is an issue in some stands. The susceptibly of Pinus muricata to needle blight caused by Dothistroma septospora varies geographically (Ades et al. 1992). Trees in the northern populations (Humboldt, Mendocino, and Sonoma counties) are moderately susceptible for the first 5 years of life. Those from Marin County south are increasingly susceptible. Trees on Santa Rosa Island are resistant. In addition, ectomychorrhizal fungi are symbiotically associated with stands, and the fungi vary significantly in species composition when comparing colonizing and mature stands (Taylor and Burns 1999). On the islands, Pinus muricata is a relatively short-lived tree, living up to 65 years. The alliance on the islands appears to be in decline, likely because of browsing by grazers. The relative lack of fire on the islands may also limit reproduction, since the cones readily open in the presence of high temperatures. Several populations have shown recovery since the removal of herbivores from both Santa Cruz and Santa Rosa islands.
Pitch pine canker (Fusarium subglutinis f. sp. pini) is an issue in some stands. The susceptibly of Pinus muricata to needle blight caused by Dothistroma septospora varies geographically (Ades et al. 1992). Trees in the northern populations (Humboldt, Mendocino, and Sonoma counties) are moderately susceptible for the first 5 years of life. Those from Marin County south are increasingly susceptible. Trees on Santa Rosa Island are resistant. In addition, ectomychorrhizal fungi are symbiotically associated with stands, and the fungi vary significantly in species composition when comparing colonizing and mature stands (Taylor and Burns 1999). On the islands, Pinus muricata is a relatively short-lived tree, living up to 65 years. The alliance on the islands appears to be in decline, likely because of browsing by grazers. The relative lack of fire on the islands may also limit reproduction, since the cones readily open in the presence of high temperatures. Several populations have shown recovery since the removal of herbivores from both Santa Cruz and Santa Rosa islands.
Environmental Description: Climate: This alliance is found in a coastal maritime climate, occurring within 12 km of the ocean. Stands are found on headlands and low hills. Elevations range from near sea level to 450 m. In the southern portion of the range stands are found on northern exposures. Annual precipitation, in the form of rain, varies from 63-37 cm from north to south. The distinct summer dry season is ameliorated by frequent summer fogs that contribute a great deal of moisture. Throughout most of this alliance''s range, three-quarters of summer days are foggy. It is found primarily on upper positions of a slope, though occasionally lower and in canyons, at predominately north-facing, cooler aspects.
Soil/substrate/hydrology: Stands occur on a variety of substrates, including diatomaceous shales, weathered basalt, and old beach sand deposits. All these soils are shallow, acidic, and poorly drained. On the Channel Islands, soils are derived from a variety of substrates but primarily schists or sandstones, and textures include moderately fine sandy clay loam. On the mainland, the soils are podzolized and flooded with perched water over an iron hardpan in the B horizon. Diatomaceous soils have a high water-retaining capacity.
Soil/substrate/hydrology: Stands occur on a variety of substrates, including diatomaceous shales, weathered basalt, and old beach sand deposits. All these soils are shallow, acidic, and poorly drained. On the Channel Islands, soils are derived from a variety of substrates but primarily schists or sandstones, and textures include moderately fine sandy clay loam. On the mainland, the soils are podzolized and flooded with perched water over an iron hardpan in the B horizon. Diatomaceous soils have a high water-retaining capacity.
Geographic Range: This alliance of the maritime zone is found discontinuously along the northern and central California coast, from Humboldt to Santa Barbara. Stands are also found on the Channel Islands, and on Guadalupe Island in Baja California, Mexico.
Nations: MX,US
States/Provinces: CA, MXBCN, OR?
Plot Analysis Summary:
http://vegbank.org/natureserve/ELEMENT_GLOBAL.2.907149
Confidence Level: Low
Confidence Level Comments: No Data Available
Grank: G3
Greasons: No Data Available
| Type | Name | Database Code | Classification Code |
|---|---|---|---|
| Class | 1 Forest & Woodland Class | C01 | 1 |
| Subclass | 1.B Temperate & Boreal Forest & Woodland Subclass | S15 | 1.B |
| Formation | 1.B.1 Warm Temperate Forest & Woodland Formation | F018 | 1.B.1 |
| Division | 1.B.1.Nc Californian Forest & Woodland Division | D007 | 1.B.1.Nc |
| Macrogroup | 1.B.1.Nc.1 California Live Oak - California Laurel - Western Cypress species Forest & Woodland Macrogroup | M009 | 1.B.1.Nc.1 |
| Group | 1.B.1.Nc.1.b Western Cypress species - Pine species Forest & Woodland Group | G198 | 1.B.1.Nc.1.b |
| Alliance | A4097 Bishop Pine - Monterey Pine Woodland Alliance | A4097 | 1.B.1.Nc.1.b |
| Association | CEGL003076 Monterey Pine Forest | CEGL003076 | 1.B.1.Nc.1.b |
| Association | CEGL003164 Bishop Pine - Pacific Madrone / California Huckleberry Forest | CEGL003164 | 1.B.1.Nc.1.b |
Concept Lineage: includes A.121, A.125
Predecessors: No Data Available
Obsolete Names: No Data Available
Obsolete Parents: No Data Available
Synonomy: > Pinus muricata - Pinus radiata Woodland Alliance (Rodriguez et al. 2017)
> Pinus muricata (Bishop pine forest) Alliance (Sawyer et al. 2009) [87.070.00]
> Pinus radiata (Monterey pine forest) Alliance (Sawyer et al. 2009) [87.110.00]
> Monterey Pine Forest (#83130) (Holland 1986b)
> Northern Bishop Pine Forest (#83121) (Holland 1986b)
> Southern Bishop Pine Forest (#83122) (Holland 1986b)
> Pinus muricata (Bishop pine forest) Alliance (Sawyer et al. 2009) [87.070.00]
> Pinus radiata (Monterey pine forest) Alliance (Sawyer et al. 2009) [87.110.00]
> Monterey Pine Forest (#83130) (Holland 1986b)
> Northern Bishop Pine Forest (#83121) (Holland 1986b)
> Southern Bishop Pine Forest (#83122) (Holland 1986b)
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