Distribution

Endemic to Mexico occurring in the Sierra Madre Occidental, in Chihuahua, Sinaloa, Durango, Nayarit, Jalisco, Zacatecas, Aguascalientes and Guanajuato. In DUrango it is one of the five most common pine species (Silva-Flores et al. 2014)

It is usually found scattered among other pines and often less abundant. According to the Mexican National Forest and Soil Inventory, the at least 2500, potentially up to 60,000, tiny to small sad pine stands cover a total area of about 1,600,000 ha with an average distance of 0.5–2.5 km among stands (CONAFOR 2009 in Reyes-Murillo et al. 2016). Some decline is likely due to extensive logging of pine forests in general. However, the extent of the impact on this species is unknown.

Habitat and Ecology

The altitudinal range of this species is (1,500-)1,700-2,600(-2,900) m a.s.l., which corresponds to the lower and middle slopes of the Sierra Madre. It grows usually mixed with several species of Quercus and other pines in pine-oak forest, or on the wetter western slopes of the Sierra Madre, in mixed pine forest. Associated pines are e.g. P. leiophylla, P. arizonica, P. douglasiana, P. teocote, and P. oocarpa; on more mesic sites one can expect P. ayacahuite and Pseudotsuga menziesii, while in dry habitats Pinus cembroides can occur with it. The annual precipitation, mostly as summer rains, is a moderate 500-600 mm (except on the driest and wettest sites). Additional species it can be associated with are Pinus herrerae, P. luzmariae, P. praetermissa, P. durangensis, Quercus urbanii, Q. crassifolia, Q. coccolobifolia, Q. rugosa, Q. magnoliifolia, Q. viminea.

Pure stands are usually found on strongly acidic bright white shallow soil; the pendulous foliage may be an adaptation to heat or solar radiation which is strongly reflected by the underlying soil (Reyes-Murillo et al. 2016).

Conservation Status

Global Status

Near Threatened

Global Rationale

Although widespread, with an extent of occurrence (EOO) far beyond the threshold for a threatened category, this species is probably in decline due to logging. The area of occupancy is also beyond the thresholds. Past and recent exploitation may be approaching the required thresholds.

Conservation Actions

This species is present in several protected areas. Recent surveys have recommended the establishment of a network of P. lumholtzii seed stands with a maximum distances of 100 km between stands to prevent greater loss of local genetic variants. Local reforestation project should source their seeds within 50 km of the restoration site (Reyes-Murillo et al. 2016).