Climate—Growth Relationships of Pinus rigida (Mill.) at the Species' Northern Range Limit, Acadia National Park, ME

This study examined climate-tree growth relationships of a G2 globally rare Pinus rigida (Pitch Pine) barren located at the species' northern range limit in Acadia National Park, ME. Our tree-ring chronologies spanned the period 1804-2014 CE and included 50 dated tree-ring series from 33 trees. We found significant (P < 0.05) positive correlations in all chronologies between each year's tree growth and previous October through April temperature, as well as with August precipitation. Additionally, we found negative correlations between our chronologies and previous July precipitation. Moving interval correlation analysis showed temporal instability of all climate-growth relationships except for April temperature and August precipitation for the total width and latewood chronologies. Our results corroborate previous findings that suggest tree species at their northern range limit respond positively to winter temperature. We posit warmer winter temperatures and enhanced late-summer precipitation indicate a maritime influence that positively influenced radial growth at our site.