Members of the Wooster Tree Ring Lab had a great opportunity to travel to a seldom-visited part of Glacier Bay National Park and Preserve – a transect from Wolf Lake to Burroughs Glacier. We were there because there is 2500 year-old forest remnant that was overrun by ice. The ice has gone and continues to melt. Our interest is recovering these logs is to fill a gap millennial-scale tree-ring record from the Gulf of Alaska. The recently exposed logs are being lost to science each year as they flush out into the sea and rot away in this hypermaritime climate. Wooster student independent studies (ISs) in the region quite literally have surrounded this Wolf Lake site with their research, and over the last 10 years we have honed into this key location from all directions.
A view of Mount Wright through a gap in drift and bedrock. Tree-ring records from the flanks of Mt. Wright were part of a study led by Stephanie Jarvis and sampled by Sarah Appleton, who did their thesis work in the region.
We flew into the site this year. In previous years we attempted to walk in twice and once we were successful. I recommend the flying
The group shown coring a Sika spruce just outside of town.
More coring – this time in the rain.
The steep climb up the flank of Ear Mountain to find the old Mountain Hemlocks.
Comparisons of the fast growing Sitka Spruce and the slow growth of the higher elevation Mountain Hemlock.
The cores from the hemlock some over 400 years old show lots of stress , clinging to the mountain side and battered by storms. They are also showing a possible drop in ring-width over time 
So we measured the ring-widths (Nick Wiesenberg and Melita Wiles did) and then we compiled the ring-width data into a chronology above. This chronology is the full record going back into the 16th century
This chronology is truncated at 1720 or so when we had at least 4 samples. The most narrow rings follow the 1808 unknown eruption that cooled much of the region – it is unknown as no one knows where the volcano that erupted is located – it is recognized in ice cores. The other intriguing feature is the relatively recent (last 50 year) drop in ring widths. It may be due to increased evapotranspiration demands with increasing summer minimum temperatures. There is a correlation of -0.39 (p<0.04) between tree growth and average April-August minimum temperatures. Other studies have shown that warming night time temperatures lead to increased respiration at night and along with possible greater ET demand or increased cloudiness during the day there may be a decrease in photosynthesis leading to decreased carbon uptake (Sullivan et al., 2015). This is a promising line of research to further investigate the health of Mt. Hemlock in the region and it is something we plan to pursue with more samples in the future. 
View from Ear Mountain looking north.