The Wooster Tree Ring Lab is part of the international tree-ring community, that investigated the global extent and seasonal timing of the rapid increase in atmospheric 14C concentrations from the two largest cosmogenic events in 774 and 993 CE. The initiative named “COSMIC” is lead by Ulf Büntgen (Cambridge University), Lukas Wacker, and J. Diego Galván (Swiss Federal Research Institute WSL) and measured these two cosmogenic events in 44 of the world’s longest tree-ring chronologies. These events are now key marker years and a powerful dating tool. The study was published in Nature Communication and can be found here.
Results of fieldwork in Glacier Bay National Park and Preserve by collaborators from Lamont-Doherty Earth Observatory and University of Alaska – Fairbanks are described here in this excellent blog. This narrative is written by scientist, author and collaborator on the project Lauren Oakes. Lauren is also author of a forthcoming book on Alaska Cedar Decline and Climate.
Coring a white oak that is slated for removal – we learned a lot from the group. For example, Volcano munching was a topic of conversation a concept we which were not aware.
More coring – Nick then took the group to the wood shop and lab.
Mounting the cores – we look forward to working with the group next year. The Tree Corp Program in its inaugural year seemed a major success – congratulations.
Summer 2018 research in the Tree Ring Lab has come to a close. The group of five students worked on a variety of projects, learning about the climate and history of Ohio and Alaska, and the application of different dendrochronological techniques and statistical analyses. They also gained experience effectively conveying their research to others and writing official reports of their findings.
The summer research team on their last day working together (Left to right: Greg Wiles, Nick Wiesenberg, Victoria Race ’19, Juwan Shabazz ’19, Kendra Devereux ’21, Josh Charlton ’19, and Alexis Lanier ’20).
AMRE students with a sampled oak tree at Brown’s Lake Bog in Wooster, Ohio (Alexis Lanier ’20, Juwan Shabazz ’19, and Kendra Devereux ’21).
The AMRE team accomplished a lot during the eight weeks they were here on campus. Their research started with the principles of dendrochronology, when they learned how to count individual tree rings and measure their widths under the microscopes. From here, the team learned how to run this data in different programs like COFECHA and ARSTAN. This process allowed them to date many historical structures across Northeast Ohio such as Gingery Barn and Miller House and Barn. You can find a full list on the TRL’s reports page.
AMRE students with
Today is the official last day for AMRE researchers here at the Tree Ring Lab. The AMRE team has accomplished many projects these past 8 weeks.
Their research started with the principles of dendrochronology, when they learned how to count individual tree rings and measure their widths under the microscopes. From here, the team learned how to run this data in different programs like COFECHA and ARSTAN. This process allowed them to date many historical structures across Northeast Ohio such as Gingery Barn and Miller House and Barn. You can find a full list on our reports page.
The AMRE students also learned how to take these chronologies and make hypotheses regarding past climate by uploading the data to Climate Explorer and running various correlations with other datasets.
We were fortunate enough to go out in the field and personally collect most of the data that we worked with this summer. These eventful trips included a lot of tree coring and required lots of bug spray. Some of the AMRE group’s favorites trips included Stebbin’s Gulch and Brown’s Lake Bog.
The other two summer researchers working in the Tree Ring Lab this summer, Victoria Race and Josh Charlton, have been working with tree ring data collected from Alaska. Their work focuses on the modeling of Columbia Glacier located in Prince William Sound, Alaska. They are currently working on an abstract to submit to the upcoming GSA conference this fall. Stay tuned for more information regarding their project!
Special thanks to the National Science Foundation, the Sherman Fairchild Foundation and the AMRE program for helping to make this research possible. Enjoy the rest of your summer!
Summer researchers working in the Tree Ring Lab returned to Stebbin’s Gulch in late May to collect more chestnut oak samples. This increased replication helps us to strengthen our various hypotheses made from the interpretation of our findings.
This information is useful in mapping out land use changes in Northeast Ohio. The team identified an abrupt increase in ring width around 1840. They attributed this rise to decreased competition from logging which coincides with the time of most significant settlement in the area.
Read more about their conclusions in the official dendroclimatological report here.
The team collected cores from white and red oak trees at both locations to update their chronologies and analyze land use history of these areas.
Barnes Preserve is a 76-acre park known for its rejuvenating atmosphere, diverse wildlife, and accessible trails. The team focused on collecting samples from mature trees in order to create a new local chronology. The Tree Ring Lab hopes to return to Barnes Preserve and build upon this record in the future.
The Wilderness Center has an old growth forest named Sigrist Woods that the team was interested in sampling. From these cores they hoped to learn more about a recent storm that damaged and felled many trees in the area. They plan to look more closely at the cores to see if ring widths were affected by this event by either storm damage or loss of competition.
Preliminary results are showing that the trees from Sigrist are dating back to the late 1800’s. Stay tuned for more of their results!
Special thanks for Denny Jordan and Herb Broda for helping facilitate this research.
Brown’s Lake Bog, located near Shreve in Wayne County, Ohio, is a nature preserve and National Natural Landmark that was established in the 1960’s. College of Wooster students have been involved in several past projects at Browns Lake Bog including sediment coring and ice drilling. Last week, the 2018 AMRE students ventured to this local spot to collect tree cores from some red and white oaks in order to perform some climate analysis for the Nature Conservancy and the Friends of Brown’s Lake Bog.
Brown’s Lake Bog is one of a few remaining peatland sites across Ohio that contains an open kettle lake surrounded by a floating sphagnum moss mat. These features are glacial relicts and the knolls surrounding the bog are glacially-formed hills called kames.
This field site is known for its diverse and rare plant community which thrives in the bog’s special acidic and nutrient-poor environment. More than twenty rare plant species can be found here. The carnivorous Northern Pitcher Plant (Sarracenia purpurea) is one of the rare species that attracts bog visitors.
After checking out the kettle lake, the tree ring lab group hiked the short trail to reach the trees sitting on top of the kames. The AMRE students sampled 6 of the oldest white and red oak trees.
Upon returning to the lab, the group mounted up the fresh cores and prepared them for counting and measuring ring widths. This week, Kendra and Alexis are working to update the local chronology and perform various correlations with the data. The final product will be an official climate analysis report.
The map below displays a positive correlation between ring width and precipitation during the months of June and July in the local Wooster area. These months displayed the highest p values and correlations (as shown in the bar graph), which is why these months were selected while creating the map using Climate Explorer. A positive correlation suggests that the more it rained, the better the trees grew (this is expressed in wider ring widths).
Stay tuned for more of their results!
Read our complete dendroclimatological report here.
Summer researchers have started a new project!
Last Wednesday, the AMRE group met with Ray Leisly at Sonnenberg Village in Kidron, Ohio.
Mr. Leisly brought the group to three different historical structures, including two homes and one barn. The families who own these structures are interested in learning how old their historical buildings are.
The group collected around 15 cores from each structure, using both hand borers and an electric drill with a hollow drill bit. This process is more thoroughly outlined in our Gingery Barn post.
On Thursday, the group returned to the lab to finish preparing the samples. Nick Wiesenberg used the belt sanders while Kendra and Juwan hand-sanded each core. This process helps to expose the ring boundaries so they can be more easily counted and measured under the microscope.
The team is currently analyzing each core by counting the number of rings, measuring ring widths, and comparing this data to a master chronology. Cross-dating will allow us to obtain the date that each tree was cut down, which will then indicate how old each historical structure is. Soon we will be able to report to our clients with details on our findings and a calendar date for when their buildings were constructed.
Stay tuned for updates!