Comparison of postfire mortality in endemic Corsican black pine (Pinus nigra ssp. laricio) and its direct competitor (Pinus pinaster)

Pimont F., Prodon R., Rigolot E. 2011. Comparison of postfire mortality in endemic Corsican black pine (Pinus nigra ssp. laricio) and its direct competitor (Pinus pinaster). Annals of Forest Science, Vol. 68, Issue 2, pp 425-432.

Abstract

Introduction
Laricio pine (Pinus nigra J.F. Arn. ssp. laricio (Poiret) Maire var Corsicana Hyl.) is a form of black pine endemic to Corsica, that may now be under threat due to current fire regimes and competition with maritime pine (Pinus pinaster Aiton).

Material and methods
This study aimed to compare postfire mortality in laricio and maritime pine in a mixed stand in northwest Corsica. Diameter at breast height, bark char, bole length charred, and tree mortality were measured in 661 trees 9 months after a severe fire. Logistic regressions were used to determine mortality probabilities which, to compare the two species, were expressed in relation to species, age, and species-independent severity indicators.

Results
For all ages considered, laricio pine mortality was up to threefold that of maritime pine. The differences between the species were most significant in pines less than 60 years old and exposed to severe conditions. This was mainly due to differences in growth rate between the two species.

Conclusion
Considering life history traits, maritime pine appears to be better adapted than laricio pine to the risk of fire. As the frequency of major fires in Corsica is on the increase, constituting a real threat for endemic species, we provide a few management guidelines for conservation of the laricio pine.