Pinus durangensis | Threatened Conifers of the World (en-GB)

Pinaceae

Pinus durangensis Martínez

An important timber species in the Sierra Madre Occidental of Mexico. Over exploitation is leading to a decline that could be sufficient to warrant a threatened category in the near future.

Distribution

Mainly in the southern Sierra Madre Occidental of Mexico, rare in E Sonora and Chihuahua, common in Durango, Zacatecas and N Jalisco, more scattered further south in Jalisco and N Michoacán

Populations have been substantially reduced within the last 25 years due to exploitation, fires and forest clearance. The decline is ongoing.

Habitat and Ecology

In the Sierra Madre this species is an important constituent of the 'yellow pine' forest, where it occurs in pure stands or mixed with several other species of pine, e.g. P. arizonica, P. leiophylla, and P. engelmannii, or in pine-oak forests. Its altitudinal range is extensive: (1,400-) 1,600-2,800 (-3,000?) m, but it is most common at 2,000-2,800 m a.s.l. Climatically, the Sierra Madre is warm-temperate, but with cold spells during the short winter at the higher elevations. Annual precipitation varies between 700-1,200 mm, most of which occurs in the summer. This pine is adapted to grow on shallow, rocky soils, but its better stands are found on deeper soils, where it can successfully compete with most other pines. The soils are mostly derived from volcanic rock. At the highest elevation P. durangensis occurs with Abies and/or Cupressus lusitanica, at the lowest with Juniperus deppeana and Pinus oocarpa. Other pines are P. montezumae, P. teocote and in the southern part of its range P. ayacahuite can occur with it. In addition this species is associated with Quercus sideroxyla, Q. rugosa, P. ayacahuite and Pseudotsuga (Garcia and Gonzalez 2003).

Human Uses

Durango Pine is an important timber tree. It grows straight and tall and is (or was) abundant and wide spread in many areas within its range. Logging from natural stands at the current rate is unsustainable and plantations are now being attempted in the state of Durango. Recommendations from recent research include "(i) establishing a tight network of seed stands,

with a maximum distance of 3–11 km between seed stands, to prevent greater loss of local genetic structure, and (ii) using these seeds to establish reforestations within a maximal radius of 3–5 km from seed provenances" (Hernández-Velasco et al. 2017).

The timber is used for construction such as roof beams, general carpentry, furniture, floors, and plywood.

Conservation Status

Global Status

Near Threatened

Global Rationale

The large extent of occurrence and the area of occupancy place it outside a threatened category. However, exploitation has reduced formerly “extensive pure forests in Durango and southern Chihuahua… to only scattered, open stands over most of its range” (Perry 1991). It is therefore listed as Near Threatened as it nearly meets the criteria A2cd; B2ab(ii,iii,v) for listing as threatened. Although this decline has not ceased there is insufficient data to allocate one of the threatened categories. The change in status since the previous assessment of Least Concern, can therefore be seen as a genuine recent change.

Conservation Actions

Logging should be regulated to occur at a sustainable level.

References and further reading

Carvajal, S. and McVaugh, R. 1992. Flora Novo Galiciana 17. Gymnosperms and Pteridophytes. University of Michigan Herbarium, Michigan, USA.
Farjon, A. 2013. Pinus durangensis. The IUCN Red List of Threatened Species 2013: e.T42358A2974963. http://dx.doi.org/10.2305/IUCN.UK.2013-1.RLTS.T42358A2974963.en. Downloaded on 10 August 2017
Farjon, A. and Styles, B. 1997. Pinus (Pinaceae). Flora Neotropica. Monograph 75. The New York Botanical Garden, New York.
García A., A. and González E., M.S. 2003. Pináceas de Durango. Segunda Ed. Instituto de Ecología A. C. CONAFOR.
Hernández-Velasco, J., Hernández-Díaz, J.C., Fladung, M., Cañadas-López, Á., Prieto-Ruíz, J.Á. and Wehenkel, C., 2016. Spatial genetic structure in four Pinus species in the Sierra Madre Occidental, Durango, México. Canadian Journal of Forest Research, 47(1), 73-80.
Perry, J.P. 1991. The Pines of Mexico and Central America. Timber Press, Portland