Navalacruz pine forest is the largest monospecific stand of Pinus nigra subsp. salzmannii in the Spanish central Range, as well as one of the five seed sources of its Region of Provenance. After the several large forest fires that affected other stands of this species, post-fire recruitment was extremely low, and re-planting is constrained by a chronic lack of reproductive material. Our study in Navalacruz consisted of the inventory of the more dense sector, and the threats and weaknesses for its use as seed source. The stand is considerably old and regeneration is low. However, there is wide recruitment of black pine in a close area planted about 20 years ago with Scots pine at low density. Seed collection at the mature stand is done with movable platforms carried by vehicles, which is costly due to the low accessibility. Fire risk is high due to the vicinity of unmanaged planted stands, close to a road. Another risk is genetic contamination from the plantations of unknown origin. This situation makes it necessary measures of both ex situ and in situ conservation to ensure the persistence of this relevant resource.