Austrocedrus chilensis

(D. Don) (D.Don) Pic.Serm. & Bizzarri (1978)

Common names

Chilean cedar (Vidakovic 1991), ciprès de la Cordillera.

Taxonomic notes

Syn: Libocedrus chilensis (D. Don) Endlicher (Silba 1986); Thuja chilensis D. Don; Thuja andina Poepp. and Endlicher (Vidakovic 1991).

Description

Dioecious trees (Castor et al. 1996), evergreen, with a short trunk and narrow crown. Bark red-brown, peeling in threads. Shoots dense, flat. Leaves scale-like, lateral leaves much longer than facial ones, thick, curving inwards at the pointed apex, facial leaves blunt, with an indistinct gland on the upper surface and whitish bands on the lower surface. Cones solitary, with 2 pairs of scales, the lower ones small and reflexed. Seeds small, unequally 2-winged, usually 4 to a cone (Vidakovic 1991). See García Esteban et al. (2004) for a detailed characterization of the wood anatomy.

Distribution and Ecology

Native to the mountains of S Chile and S Argentina. It occupies an exceptionally broad soil moisture gradient and, like many conifers, is exceptionally nitrogen-conservative (Buamscha et al. 1998). Forest structure has been strongly influenced by changing fire frequency and severity, with much more open stand structures during periods before European occupancy and during the early settlement period, followed by a coalescence of forest patches and increasing stand densities during the period of fire suppression (most of the 20th Century). Individual fire events are strongly influenced by climatic variables such as the ENSO (El Niño—Southern Oscillation) cycles. Both fire and grazing by introduced large herbivores (deer and cattle) are affecting current stand recruitment (Relva and Veblen 1998, Kitzberger and Veblen 1999, Veblen et al. 1999).

Austrocedrus chilensis is the most northerly distributed conifer species of the Andean Patagonian forest, with a wide latitudinal range extending between 32°40'S and 43°30'S in Chile. The northernmost populations of this species also occur, at the highest elevations reached by this species, in the Andes. These populations of Austrocedrus are growing under severe stress in low density, sparsely distributed stands (Lequesne et al. 2003).

Hardy to Zone 8 (cold hardiness limit between -12.1°C and -6.7°C) (Bannister and Neuner 2001).

Austrocedrus chilensis stands are in decline throughout the species' natural distribution, particularly among stands in poorly drained soils. Affected trees may die rapidly but mortality is commonly preceded by several decades of severely restricted radial stem growth. Roots are often affected by one or more types of decay (Filip and Rosso 1999). The problem was noted several decades ago but has only recently been found to be due to the introduced pathogen Phythophthora austrocedri. Like most species of Phytophthora, this one is innocuous in its native environment (currently unknown), but when introduced to Argentina sometime before 1948, became a serious pathogen, causing the disease mal del ciprés (MDC, cypress sickness). MDC has continued to spread since it was first discovered in Isla Victoria in Nahuel Huapi National Park (Patagonia) (Greslebin et al. 2011). By 2025, the pathogen had also appeared in the UK, Norway, and Iran, where it primarily affects horticultural conifers including Callitropsis nootkatensis, Cupressus sempervirens, and Juniperus communis (Green 2018). Given the variety of affected taxa, it potentially threatens a large number of species in the Cupressaceae.

Remarkable Specimens

One tree-ring sample, probably based on live tree material, is 850 years long (International Tree-Ring Data Bank, sample CHIL007, limiting dates 1131-1981). There are said to be living trees more than 1,500 years old (Lequesne et al. 2003). Tree-ring collections to date include El Asiento, (32°40'S, 70°49'W) first visited by Dr. Valmore C. LaMarche in 1972. Other sites include Rio Clarillo (33°55'S, 70°25'W); Río Cipreses and Agua de Muerte (34°27'S, 70°25'W) (Lequesne et al. 2003).

Ethnobotany

It has been used in a variety of dendrochronology studies since the early 1970s. Preexisting chronologies have been used to develop a long reconstruction of drought severity in central Chile (Lequesne et al. 2003) and a long reconstruction of Chilean streamflow (Urrutia et al. 2003). Ring anatomy has provided information on the past occurrence of late-spring frost events (Muñoz-Salazar et al. 2022).

Observations

Remarks

Austrocedrus means "southern cedar" and chilensis means "of Chile."

Citations

Buamscha, G., M. Gobbi, M.J. Mazzarino, and F. Laos. 1998. Indicators of nitrogen conservation in Austrocedrus chilensis forests along a moisture gradient in Argentina. Forest Ecology and Management 112(3): 253-261.

Castor, C., J.G. Cuevas, M.T.K. Arroyo, Z. Rafii, R. Dodd and A. Penaloza. 1996. Austrocedrus chilensis (D. Don) Pic-Ser et Bizz (Cupressaceae) from Chile and Argentina: Monoecious or dioecious? Revista Chilena de Historia Natural 69(1): 89-95.

Florin and Boutelje. 1954. Acta Horti Berg. 17:28.

Green, S. 2018. Phytophthora Austrocedri. CABI Compendium 108927. https://doi.org/10.1079/cabicompendium.108927.

Greslebin, A., Hansen, E. M., and La Manna, L. 2011. Phytophthora austrocedrae. Forest Phytophthoras 1(1). doi: 10.5399/osu/fp.1.1.1806. Available http://forestphytophthoras.org/species/austrocedrae, accessed 2013.11.16.

Kitzberger, T. and T.T. Veblen. 1999. Fire-induced changes in northern Patagonian landscapes. Landscape Ecology 14(1): 1-15.

Lequesne, Carlos, J.C. Aravena, A. Lara and J.A. Boninsegna. 2003. Central Chile drought reconstruction using tree-ring chronologies: A preliminary report. P. 21 in Programme with Abstracts, Fourth Annual Science Meeting, IAI CRN 03: The Assessment of Past, Present and Future Climate Variability from Treeline Environments. IANIGLA-CRICYT, Mendoza, Argentina, October 10-16, 2003.

Muñoz-Salazar, Tomás, Carlos LeQuesne, Vicente Rozas, Duncan A. Christie, and Moisés Rojas-Badilla. 2022. Examining the potential of Austrocedrus chilensis tree rings as indicators of past late-spring frost events in central Chile. Dendrochronologia 125962.

Pichi Sermolli, R. and M. Bizzarri. 1978. Webbia 32(2):482.

Relva, M.A. and T.T. Veblen. 1998. Impacts of introduced large herbivores on Austrocedrus chilensis forests in northern Patagonia, Argentina. Forest Ecology and Management 108(1-2): 27-40.

Urrutia, R., A. Lara, R. Villalba, L. Pezoa, C. Lequesne, E. Cuq and A. Wolodarsky-Franke. 2003. Streamflow reconstruction from tree-ring chronologies of Austrocedrus chilensis and Pilgerodendron uviferum in the Xth Region, Chile. P. 39 in Programme with Abstracts, Fourth Annual Science Meeting, IAI CRN 03: The Assessment of Past, Present and Future Climate Variability from Treeline Environments. IANIGLA-CRICYT, Mendoza, Argentina, October 10-16, 2003.

Veblen, T.T., T. Kitzberger, R. Villalba, and J. Donnegan. 1999. Fire history in northern Patagonia: The roles of humans and climatic variation. Ecological Monographs 69(1): 47-67.

See also

Elwes and Henry 1906-1913 at the Biodiversity Heritage Library (as Libocedrus chilensis). This series of volumes, privately printed, provides some of the most engaging descriptions of conifers ever published. Although they only treat species cultivated in the U.K. and Ireland, and the taxonomy is a bit dated, still these accounts are thorough, treating such topics as species description, range, varieties, exceptionally old or tall specimens, remarkable trees, and cultivation. Despite being over a century old, they are generally accurate, and are illustrated with some remarkable photographs and lithographs.

Farjon (2005) provides a detailed account, with illustrations.