| Riassunto: | The Presidio San Pedro basin yields the water of one the main streams draining to Marismas Nacionales in the states of Sinaloa and Nayarit. A dominant conifer species on this watershed is Pinus durangensis a heavily logged species such that old-growth forest has disappeared. Increment cores from 63 trees of P. durangensis in a low disturbed site were extracted to analyze its dendrochronological potential. The samples were processed by standard dendrochronological techniques. Series intercorrelation (0.463), mean sensitivity (0.309), first order autocorrelation (0.41), and signal to- noise ratio (5.24) among other parameters indicated excellent potential of the species for dendrochronological purposes. Time series of earlywood, latewood and total ring width were developed with a length of 232 years (1780-2012). The earlywood chronology responded to the accumulated January-August precipitation from four weather stations in the watershed and a linear regression model was used to reconstruct seasonal winter to early summer precipitation. Similar to other previous climatic reconstructions for the Presidio San Pedro basin, ENSO was the most influential phenomena on explaining the interannual and multiannual variability. It was not found a significant relationship between latewood indices and summer precipitation indicating low inter-annual variability of the North American Monsoon System, even though this phenomenon causes over 70% of the annual precipitation on this region.
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