Fitzroya cupressoides (Molina) I.M.Johnst.

Cupressaceae

A genus with a single species endemic to Argentina and Chile where it is globally threatened by selective logging, grazing and fire

Associated Names:

alerce and lahuén

Description

Habit

Large evergreen tree to 50m, dioecious or rarely monoecious; pyramidal or sometimes stunted into low shrubs at high elevations. Trunk 2.5–5m in diameter; bark brownish red, deeply furrowed, fibrous.

Foliage

Leaves arranged in alternating whorls of three, rarely in twos or fours, deep green or glaucous, of two types: i) on mature branches 2.5–3mm long, scale-like, ovate, tightly imbricate, keeled and with a narrow decurrent base ii) on immature branches spathulate 5–8mm long, falcate and flattened. Stomata arranged in bands near the margin and keel, on both surfaces of the leaf.

Cones

Male pollen-cones terminal, solitary on short axillary branches, 6–8mm long, yellowish white.8mm long, yellowish white. Female seed-cones globose, 6–8mm, solitary, terminal on short lateral shoots, green at first, maturing brown with 6–8 woody scales in alternating whorls of 3, each scale with a prominent umbo. Seeds 2–3mm in diameter, each with 2–3 wings; maturing from February to March.

Key characters

Fitzroya could be confused with Pilgerodendron uviferum. In Fitzroya the leaves are usually arranged in alternating whorls and are of two types: scale-like and strongly keeled on mature branches, falcate and flattened on immature branches. All leaves have two obvious white stomatal bands on the underside. In Pilgerodendron the leaves are regularly arranged in decussate pairs, incurved, triangular and keeled on the back.

Distribution

Endemic to southern Argentina and Chile where it has a discontinuous distribution from 39°50’ to 43°30’S. In Chile it occurs in Region X from Province Valdivia (39°50’S) to Province Palena (43°30’S). It is found in the Coastal Cordillera from 39°50’S to 42°35’S; the Central Valley from 41°30’ to 41°50’S and in the Andes from 40°50’ to 43°30’S. In Argentina it occurs in the Provinces of Chubut, Neuquén and Río Negro from 40°57' to 42°45'S. In both Chile and Argentina it has a discontinuous distribution in the Coastal Cordillera (Chile), the Central Valley (Chile) and the Andes (Chile and Argentina) with an altitudinal range of 1–1,500m. Patterns of intraspecific variation in Fitzroya have been studied with different molecular markers (isozymes and RAPDs) along the range of the species in Chile and Argentina. Populations located on eastern and western slopes of the Andes are genetically distinct with eastern populations carrying higher levels of genetic variation than western ones (Allnutt et al., 1999; Premoli et al., 2000).

Habitat and Ecology

Fitzroya usually grows on poorly drained young soils (Veblen et al., 1995) derived from volcanic ash (Peralta et al., 1979; Conaf, 1985; Kühne, 1985). At low and middle elevations, it occurs on poorly drained sandy soils, rich in organic matter, low pH and high C/N rate (Peralta et al., 1979). At higher altitude (800–1,200m.) it grows on insipid soils, also derived from volcanic ash, but sandy well drained and infertile (Peralta et al., 1979). These areas receive between 2,000–4,000mm precipitation per annum (Donoso 1981; Villalba 1990; Lara 1991). Throughout its range Fitzroya grows in a range of forest types. For instance in Chile, at elevations greater than 800m it is often associated with Nothofagus betuloides, while at mid-elevations of from 500–800m it grows with Nothofagus nitida, Pilgerodendron uviferum, Podocarpus nubigenus and Tepualia stipularis. At low elevations of between 40 and 500m Fitzroya is uncommon and typically grows as a large tree in the Valdivian rainforest with Amomyrtus luma, Drimys winteri, Laureliopsis philippiana, Saxegothaea conspicua and Weinmannia trichosperma (Hechenleitner et al., 2006).

A very long-lived, slow growing tree with records of it living for more than 3,600 years old (Lara and Villalba, 1993). It is a dioecious species or occasionally monoecius (Rodríguez et al., 1983). Inter-annual seed production is highly variable, with 5–7 years periods of low to no production and viability is also usually low (Donoso,1995). In the Chilean Andes most Fitzroya-dominated forests have originated following large-scale disturbance such as volcanic ash depositions, lava flows and landlslides. It can resprout from roots or low branches (Veblen & Ashton, 1982).

Human Uses

Despite national and international legal protection, particularly in Chile, its timber has continued to be exploited and this is reflected in the fact that during 1977–1996 the export value of alerce timber reached an average of US $865,000 (Díaz et al.,1997). Logging permits are issued for timber declared to originate from trees that died prior to 1976 when alerce was declared a National Monument and the cutting of live tres prohibited. Determining the date of death can be problematic and there have been many instances of fires being deliberately set in forests in the Chilean Andes and Coastal ranges in order to produce more dead timber for harvesting (Lara et al., 2003; Wolodarsky & Lara, 2005).

Conservation Status

Global assessment

Endangered A2acd

Global rationale

Although the estimated 42% past reduction in its area of occupancy does not meet the 50% threshold for A2 under Endangered, there has been an estimated reduction in the quality of habitat across its total range of more than 50% during the last three generations. In Chile, where most of the population occurs, this is very evident in the Coastal Cordillera where most of the alerce forests comprise secondary forest that is the result of fire, logging and damage to trees from bark stripping for caulking purposes. The majority of the Andean forests been impacted in similar ways. The decline in habitat quality is ongoing as illeagl logging continues and deliberately set fires re-occur.

Global threats

For more than three centuries Alerce has suffered from over-exploitation due to its highly prized wood; human-set fires and conversion of forest to pasture land has significantly reduced its range and left extensive deforested or degraded areas Veblen, et al., 1976, 1982). In Argentina 60% of the subpopulations shows signs of anthropogenic disturbances linked with cattle ranching and browsing, however, the present-day situation is that the remaining forest are in a relatively good conservation state (Kitzberger, et al., 2000). In Argentina, since the 1980s, there has been little illegal exploitation of Fitzroya. Destruction in Chile's Central Depression has been extensive and until 1987, the tree was believed to have been completely eliminated from this area (Lara et al., 2003). During the summer of 1997–1998, human-set fires destroyed 9,777ha in Chile's Coastal Cordillera. Fires in alerce forests represented 34% of all forest fires in the provinces of Valdivia and Llanquihue in the 1997-98 summer (CONAF, 1998). Throughout its range there has been a 42% loss of the original cover from 617000 to 265000 ha (Lara, 2008), but the decline in habitat quality is far greater (exceeding 50%): evidence for this can be found in the large areas of existing forest with a high percentage of burnt trees in the Coastal Cordillera and the many Andean sites which show poor regeneration and growth and also have a history of selective logging and fire.

Conservation Actions

In 1973 Fitzroya was included under Appendix I of CITES. In 1976, it was declared a National Monument and the exploitation of live trees was prohibited. In 1979 it was included as a threatened species under the Endangered Species Act in the United States, forbidding its import to that country. In Chile, 47,400ha (17%) out of a total of 264,993ha of Fitzroya forests are protected within National Parks and National Reserves. The remaining 83% of Fitzroya forests is mainly within private properties (Lara, 2008). The largest is Pumalín Park, which in its 250,000ha contains significant alerce forests. In Argentina over 80% of Fitzroya forests occur in protected systems (Premoli, 2000). Researchers from Universidad Austral de Chile are carrying out ecological restoration of Alerce in the Central Depression using nursery-grown seedlings of local provenances in association with a small land owner and the regional office forest service. Population genetic research has shown that two southern Argentinean populations (Río Tigre and Lago Esperanza) hold genetic "hot spots" for the species (Premoli et al., 2000) and the loss of these subpopulations could result in the loss of significant genetic diversity. The remoteness and relatively small size of these subpopulations has meant that they are almost untouched and are representative of Fitzroya forests prior to European colonisation and subsequent exploitation. However, these subpopulations are outside of any protected area. The creation of new protected areas, to preserve the populations of Río Tigre and Lago Esperanza in Argentina is an urgent task (Donoso et al., 2006). The long term conservation of Fitzroya forests is a great challenge that requires the agreement of numerous social actors and the active participation of individuals, indigenous communities, companies, and the national states from Chile and Argentina.