Print Report
A4221 Pinus torreyana Woodland Alliance
Type Concept Sentence: This alliance is composed of stands dominated by Pinus torreyana, a rare conifer, on windswept coastal bluffs in southern California.
Common (Translated Scientific) Name: Torrey Pine Woodland Alliance
Colloquial Name: Torrey Pine Woodland
Hierarchy Level: Alliance
Type Concept: This alliance is composed of stands dominated by a rare conifer on windswept coastal bluffs in southern California. Stands are characterized by an open to scattered tree canopy (10-35% cover) of Pinus torreyana. Pinus torreyana is the sole dominant in the tree canopy and is often emergent over a shrub canopy with Adenostoma fasciculatum, Artemisia californica, Baccharis pilularis, Ceanothus arboreus, Ceanothus verrucosus, Cneoridium dumosum, Coreopsis gigantea, Coreopsis maritima, Eriogonum fasciculatum, Heteromeles arbutifolia, Quercus berberidifolia, Rhus integrifolia, and Salvia species. Trees are <15 m tall and the canopy is intermittent or open. The shrub layer is sparse to intermittent. Herbaceous layer is sparse or abundant. Stands occur on coastal bluffs, maritime terraces, and slopes. Soils are sandstone or diatomaceous-derived, and the elevation ranges from sea level to 175 m.
Diagnostic Characteristics: No Data Available
Rationale for Nominal Species or Physiognomic Features: No Data Available
Classification Comments: Mainland and island populations have few species in common (Philbrick and Haller 1988, Vogl et al. 1988). Three populations of Pinus torreyana exist with about 9000 trees. The two subspecies of Pinus torreyana differ in needle and cone characters (Haller 1967). Both subspecies are rare, CNPS List 1B plants (CNPS 2001).
Similar NVC Types: No Data Available
note: No Data Available
Physiognomy and Structure: No Data Available
Floristics: Pinus torreyana is dominant in the tree canopy or is emergent over a shrub canopy with Adenostoma fasciculatum, Artemisia californica, Baccharis pilularis, Ceanothus arboreus, Ceanothus verrucosus, Cneoridium dumosum, Coreopsis gigantea, Coreopsis maritima, Eriogonum fasciculatum, Heteromeles arbutifolia, Quercus berberidifolia, Rhus integrifolia, and Salvia species. Trees are <15 m tall and their canopy is intermittent or open (10-35%). Shrub layer is sparse to intermittent. Herbaceous layer is sparse or abundant. On Santa Rosa Island additional understory shrubs include Lotus dendroideus var. dendroideus (= Acmispon dendroideus var. dendroideus), Arctostaphylos confertiflora, Diplacus parviflorus (= Mimulus aurantiacus var. parviflorus), Baccharis pilularis (= ssp. consanguinea), Eriophyllum confertiflorum var. confertiflorum, and Quercus pacifica. Common herbs include Achillea millefolium, Bromus diandrus, Carex globosa, Corethrogyne filaginifolia, Pentagramma triangularis, Pseudognaphalium biolettii, Agrostis pallens, Avena sp., Bromus madritensis, Festuca sp., Gamochaeta ustulata, Sanicula arguta, Silene laciniata var. laciniata, Achnatherum diegoense (= Stipa diegoensis), and Nassella pulchra (= Stipa pulchra).
Species of Interest: Pinus torreyana, including Pinus torreyana ssp. insularis (CRPR 1B.2) and Pinus torreyana ssp. torreyana (CRPR 1B.2), the dominant plant of this alliance, is considered rare. Lotus dendroideus var. dendroideus (CRPR 4.2), Arctostaphylos confertiflora (FE, CRPR 1B.2), and Diplacus parviflorus (CRPR 4.3) are also characteristic of the alliance. Quercus pacifica (CRPR 4.2) and Achnatherum diegoense (CRPR 4.2) are often found, while Dudleya greenei (CRPR 4.2) are Jepsonia malvifolia (CRPR 4.2) are sometimes associated with the alliance. Eriogonum grande var. rubescens (CRPR 1B.2) and Galium nuttallii ssp. insulare (CRPR 4.3) occur at less than 20% constancy in samples of this alliance.
Species of Interest: Pinus torreyana, including Pinus torreyana ssp. insularis (CRPR 1B.2) and Pinus torreyana ssp. torreyana (CRPR 1B.2), the dominant plant of this alliance, is considered rare. Lotus dendroideus var. dendroideus (CRPR 4.2), Arctostaphylos confertiflora (FE, CRPR 1B.2), and Diplacus parviflorus (CRPR 4.3) are also characteristic of the alliance. Quercus pacifica (CRPR 4.2) and Achnatherum diegoense (CRPR 4.2) are often found, while Dudleya greenei (CRPR 4.2) are Jepsonia malvifolia (CRPR 4.2) are sometimes associated with the alliance. Eriogonum grande var. rubescens (CRPR 1B.2) and Galium nuttallii ssp. insulare (CRPR 4.3) occur at less than 20% constancy in samples of this alliance.
Dynamics: Pinus torreyana is a slow-growing pine that attains an age of about 150 years. It is the rarest pine in North America, occurring as disjunct populations on the mainland and an island of southern California. Pinus torreyana has little capacity to respond to change through natural selection because of low genetic variability. Native populations need management to maintain a maximum number of trees while minimizing the chance of catastrophic loss (Ledig 1984). Infrequent, severe fires are important for seedling establishment, although disturbance is not essential (McMaster 1981). Pinus torreyana has a delayed seed response, probably in response to varying fire cycles. Seed drop from cones is substantial immediately after crown fire while some seeds gradually release from cones over 10 years after fire (McMaster 1981, 1982). Seed dispersal has been studied by Johnson et al. (2003).
Environmental Description: Stands occur on windswept coastal bluffs, maritime terraces, and slopes. Elevation ranges from sea level to 175 m. It is found on all positions of a slope on mostly northerly aspects. Soils are sandy loams derive from sandstone, diatomaceous earth, or alluvium.
Geographic Range: The alliance, as well as the species, has a very limited distribution on the California mainland near Del Mar and on Santa Rosa Island.
Nations: US
States/Provinces: CA
Plot Analysis Summary:
http://vegbank.org/natureserve/ELEMENT_GLOBAL.2.959512
Confidence Level: Low - Poorly Documented
Confidence Level Comments: No Data Available
Grank: G1
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 | A4221 Torrey Pine Woodland Alliance | A4221 | 1.B.1.Nc.1.b |
Concept Lineage: No Data Available
Predecessors: No Data Available
Obsolete Names: No Data Available
Obsolete Parents: No Data Available
Synonomy: = Pinus torreyana (Torrey pine stands) Special Stands (Sawyer et al. 2009) [87.190.00]
= Pinus torreyana Woodland Alliance (Rodriguez et al. 2017)
= Torrey pine forest (Holland 1986b)
= Pinus torreyana Woodland Alliance (Rodriguez et al. 2017)
= Torrey pine forest (Holland 1986b)
- CNPS [California Native Plant Society]. 2001. Inventory of rare and endangered plants of California (sixth edition). D. P. Tibor, convening editor, Rare Plant Scientific Advisory Committee. California Native Plant Society, Sacramento, CA. 388 pp.
- Clark, R. A., W. L. Halvorson, A. A. Sawdo, K. C. Danielsen, and C. Karen. 1990. Plant communities of Santa Rosa Island, Channel Islands National Park. Technical Report 42. University of California at Davis, Institute of Ecology, Cooperative National Park Resources Studies Unit, Davis, CA.
- Esser, L. L. 1993d. Pinus torreyana. In Fire Effects Information System [Online]. USDA, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). [http://www.fs.fed.us/database/feis/]
- Faber-Langendoen, D., J. Drake, M. Hall, G. Kittel, S. Menard, C. Nordman, M. Pyne, M. Reid, M. Russo, K. Schulz, L. Sneddon, K. Snow, and J. Teague. 2013-2019b. Screening alliances for induction into the U.S. National Vegetation Classification: Part 1 - Alliance concept review. NatureServe, Arlington, VA.
- Griffin, J. R., and W. B. Critchfield. 1972. The distribution of forest trees in California. Research Paper PSW-82/1972. USDA Forest Service, Pacific Southwest Forest and Range Experiment Station, Berkeley, CA. 114 pp.
- Haller, J. R. 1967. A comparison of the mainland and island populations of Torrey pine. Pages 79-88 in: R. N. Philbrick, editor. Proceedings of the symposium on the biology of the California islands. Santa Barbara Botanic Garden, Santa Barbara, CA.
- Holland, R. F. 1986b. Preliminary descriptions of the terrestrial natural communities of California. Unpublished report prepared for the California Department of Fish and Game, Nongame-Heritage Program and Natural Diversity Database, Sacramento. 156 pp.
- Johnson, M., S. B. Vander Wall, and M. Borchert. 2003. A comparative analysis of seed and cone characteristics and seed-dispersal strategies of three pines in the subsection Sabinianae. Plant Ecology 168:69-84.
- Junak, S., D. A. Knapp, J. R. Haller, R. Philbrick, A. Schoenherr and T. Keeler-Wolf. 2007. The Channel Islands. Chapter 9 in: M. G. Barbour, T. Keeler-Wolf and A. A. Schoenherr, editors. Terrestrial vegetation of California, third edition. University of California Press, Berkeley.
- Ledig, F. T. 1984. Gene conservation, endemics, and California''s Torrey pine. Fremontia 12:9-13.
- McMaster, G. H. 1981. Patterns of reproduction in Torrey pine (Pinus torreyana). Master''s thesis, San Diego State University, San Diego, CA.
- McMaster, G. S. 1982. Fire in the ecology and management of Torrey pine (Pinus torreyana) populations. In: E. C. Conrad and W. C. Oechel, editors. Proceedings of the symposium on dynamics and management of Mediterranean-type ecosystems; 1981 June 22-26; San Diego, CA. General Technical Report PSW-58. USDA Forest Service, Pacific Southwest Forest and Range Experiment Station, Berkeley, CA.
- Paysen, T. E., J. A. Derby, H. Black, Jr., V. C. Bleich, and J. W. Mincks. 1980. A vegetation classification system applied to southern California. General Technical Report PSW-45. USDA Forest Service, USDA Forest Service, Pacific Southwest Research Station, Berkeley, CA.
- Philbrick, R. N., and J. R. Haller. 1988. The southern California islands. Pages 893-906 in: M. G. Barbour and J. Major, editors. Terrestrial vegetation of California: New expanded edition. California Native Plant Society, Special Publication 9, Sacramento. 1030 pp.
- Rodriguez, D., K. G. Sikes, T. Keeler-Wolf, G. Kittel, J. Curtis, C. Curley, and J. Evens. 2017. Vegetation classification of Channel Islands National Park. Report to the National Park Service, Fort Collins, CO.
- Sawyer, J. O., T. Keeler-Wolf, and J. Evens. 2009. A manual of California vegetation. Second edition. California Native Plant Society, Sacramento CA. 1300 pp.
- Schoenherr, A. A., C. R. Feldmeth, and M. J. Emerson. 1999. Natural history of the islands of California. University of California Press, Berkeley, CA.
- Vogl, R. J., W. P. Armstrong, K. L. White, and K. L. Cole. 1988. The closed-cone pines and cypresses. Pages 295-358 in: M. G. Barbour and J. Major, editors. 1988. Terrestrial vegetation of California: New expanded edition. California Native Plant Society, Special Publication 9, Sacramento. 1030 pp.