Tag Archives: dendrochronology

Concluding 2018 summer of research

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.

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).

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.

AMRE students with Nick Wiesenberg collecting samples from historical structures at Sonnenberg Village in Kidron, Ohio.
Alexis and Kendra visiting one of the historical structures at Sonnenberg Village.

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.

Stebbin’s Gulch at the Holden Arboretum (Left to right: Josh Charlton ’19, Juwan Shabazz ’19, Alexis Lanier ’20, Kendra Devereux ’21, and Dr. Wiles).
Juwan with the machete, ready to clear a path for the rest of the team at Brown’s Lake Bog.
Lining up to cross the moat at Brown’s Lake Bog after a weekend of strong thunderstorms.
Kendra Devereux with the sample bag at Barnes Preserve in Wayne County.
Josh Charlton ’19 coring a tree at Stebbin’s Gulch in the Holden Arboretum.

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!

AMRE students with Victoria Race ’19 and Arrow at Brown’s Lake Bog.

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!

 

An Update on Stebbin’s Gulch at the Holden Arboretum

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.

Our views of the canopy.
Team members recording measurements and extracting a core from this living chestnut oak.
Kendra and Victoria looking at a giant burl on one of the sampled trees.
Team members coring an old chestnut oak along the gulch reaching high into the canopy.

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.

AMRE at Barnes Preserve and The Wilderness Center

Last week, AMRE students, Kendra Devereux and Alexis Lanier, ventured out to Barnes Preserve in Wooster and The Wilderness Center located in Wilmot, Ohio.

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.

AMRE students Kendra Devereux (left) and Alexis Lanier (right) coring an oak at Barnes Preserve.
Nick Wiesenberg coring a nearby tree.
A honeysuckle bush along the trail.
The team coring a fallen oak deep in the brush at Barnes Preserve.

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.

AMRE at Brown’s Lake Bog

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.

AMRE students with a sampled tree (Left to right: Alexis Lanier ’20, Juwan Shabazz ’19, and Kendra Devereux ’21)
The carnivorous Northern Pitcher Plant (Sarracenia purpurea) receives nutrients by trapping insects in its fluid-filled cavities.
The AMRE students getting coring tips from Nick.
Extracting a fresh oak core on top of the kame at Brown’s Lake Bog.
Juwan, Kendra, and Arrow sitting on a fallen oak.

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!

Correlation between ring width at Brown’s Lake Bog and precipitation records.

 

One of Kendra’s initial correlation maps created with Climate Explorer. 

Read our complete dendroclimatological report here.

Dating Historical Structures of Sonnenberg Village

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.

AMRE group and Nick Wiesenberg meet with Ray outside of Sonnenberg Church.
An example of one of the original deeds from  Miller House.

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.

Dr. Wiles using the electric drill to extract a core from a beam in Miller Barn.
Nick extracting core from overhead beam with a hand borer in Miller Barn.
Stacked beams from Zuercher house.
Freshly mounted core taken from Zuercher house beam.

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!


Follow the links to read our final reports for Zuercher House and Miller House and Barn.

Summer Researchers Start on New Project: Gingery Barn

Summer researchers in the CoW Tree Ring Lab have started a new project!

Early Wednesday morning, the group met with a new client, Don Gingery, who is interested in learning the age of his barn located in the Wooster area.

He brought in a few pieces of wood for us to check out and determine if they were good enough for processing. The oak samples did pass the test and qualified for sampling.

Some things we consider:

  • How many rings can we see with the naked eye? If there are only around 30 rings, that would not be a good sample for dating and comparing to the Ohio master chronology.
  • Is the sample whole? We look for the presence of both the outermost and inner rings to ensure we can obtain the most data. It is difficult to date structures if the outer rings are missing because we do not know exactly when that particular tree was felled.
  • Variation in ring width? The more variation between rings, the more interesting the data will be for us when looking at the tree’s relationship to precipitation records.
Oak beam sample.
The second oak sample.
Close-up prior to sanding in the lab.

To prepare the samples, Josh sanded the oak slice on the belt sander to polish its surface while Juwan and Dr. Wiles worked on obtaining a core from the other oak beam. This was done with a drill and special hollow drill bit. Two cores were extracted and immediately mounted.

Drill used for coring the beam.
Dr. Wiles aligning the drill bit prior to drilling in order to hit the heartwood and center of the rings.
Obtaining the first core.
Juwan drilling for the second core.
Obtaining the second core from the oak beam.

This drill bit is different from the hand borers used at the Holden Arboretum because it provides us with a core of a larger diameter. This is beneficial in studying the rings under the scope because we can look at a larger area of each annual ring. This drill is often used by the Tree Ring Lab when coring beams of structures rather than living trees.

The two cores extracted from the oak beam brought in by the client.
Juwan preparing the mount with wood glue.

One of the mounted cores to be left to dry.

When we returned this morning, Juwan, Victoria, and Kendra sanded and polished the two cores. Kendra is now working on measuring the ring widths under the microscope. Next steps include cross-dating and comparing these measured series to other Ohio records. We hope to then be able to provide our client with a report of our findings including a calendar date for the Gingery structure.

Stay tuned for updates!!


Our final report can be found here.

Summer 2018 Research in the CoW Tree Ring Lab

This summer, students through the AMRE program will be working in the lab doing historical dating. Kendra Devereux, Alexis Lanier, and Juwan Shabazz will be working with clients to date local barns, update chronologies, and study past climate.

Two additional students are working in the lab with data collected from Columbia Glacier in Prince William Sound, Alaska. Josh Charlton and Victoria Race will be helping out the AMRE students and also spending time with data collected from Columbia Glacier. Josh is working on constructing a model of the rapidly retreating Columbia Glacier and Victoria will be looking more closely at Blue Intensity data obtained from tree cores collected in Columbia Bay.

Work started earlier this week and the group went out in the field yesterday for the first time together. We headed up North to the Holden Arboretum to collect core samples from living Chestnut Oak trees in Stebbins Gulch.

2018 “Tree Huggers” From left to right: Victoria Race, Kendra Devereux, Alexis Lanier, Josh Charleton, and Juwan Shabazz
Alexis removing tree borer after extracting core from this chestnut oak.
Taking some measurements along with a few cores from this living chestnut oak.
Juwan and Kendra showing off their extracted cores.
Dr. Wiles checking the budding leaves of a chestnut oak.
One of our freshly extracted cores.

Today we finished mounting the cores and will begin dating them after they have been sanded. These samples will be used to update the chronology from the Holden Arboretum which has not been updated in several decades. We plan on looking specifically at precipitation data extracted from these cores and then writing an official report of our findings for the researchers at Holden.

Chestnut oak cores collected from Stebbins Gulch before mounting process.
Close-up of a damp core before mounting.

In the coming weeks, the group will be working on various projects including the Holden chronology, barn dating, and Columbia Glacier data. Stay tuned for updates!!

You can also follow the Geology Club instagram for more information and photos along with the departmental Facebook page.

The Cooper Plots – Ecological Succession in Glacier Bay National Park and Preserve, Alaska

I recently had the pleasure to work with a team of ecologists for eight days in Glacier Bay National Park and Preserve. The point of the trip was to reoccupy and expand investigations of the Cooper Plots established over 100 years ago in the wake of the retreating ice in the West Arm. A nice rundown of this ecological succession work is presented here on Glacier Hub. The ecology team recently published on their rediscovery of the plots, which was heroic considering the immense lands, intense brush and  sometimes cryptic description of the plot locations.

The accommodations and views in the West Arm of Glacier Bay were spectacular. Logistics of the project were supported by the National Park Service, who we gratefully acknowledge.

The team of ecologists included (left to right) Drs. Allison Bidlack (Director, Alaska Coastal Rainforest Center, University of Alaska Southeast), Sarah Bisbing (University of Nevada – Reno) and Brian Buma (University of Alaska Southeast). I was along to core trees at the sites (Wooster Tree Ring Lab) and to measure the size of alders.

Sarah and Brian cordon off one of Cooper’s 1-meter plots with string so we don’t trample the vegetation. Sarah reals out a 15-meter tape with Allison on……

https://woostergeologists.scotblogs.wooster.edu

Coring Brown’s Lake Bog

Two class projects kick off the Climate Change 2017 course. The first deals with tree-ring dating (dendrochronology, blog post coming soon) of historical structures and then analyzing the tree-rings for their climate significance. The second is is shown below and it concerned with analyzing sediment cores from Browns Lake Bog that document climate variability since the last Ice Age. Below are some photos of the bog coring – great thanks to Dr. Tom Lowell and his Glacial Geology class from the University of Cincinnati – the folks who did most of the work.

Setting up the coring rig at Browns Lake – early in the day snow covered the ground by 4 pm it was gone (albedo feedback in play).
The core boss (Dr. Tom Lowell) oversees the extraction of another meter of mud from the bog.
Extracting peat – the upper 5 meters or so are peat (significant amount of sphagnum moss and carbon). Note the trees, it is not a sphagnum bog now here.
Setting up the production line and assigning teams and tasks.

 

Coring a tree to determine the recruitment time – the hypothesis is that these trees moved into the bog recently (past 200 years) – the first trees here since the Ice Age. This nutrient limited bog was fertilized by wind blown dust during European Settlement allowing these vascular plants to obtain a foothold in the previously sphagnum moss dominated bog.

 

Hey there is a Wooster student – good job Ben. This white oak is growing on the top of a kame and it has witnessed the changes in the climate and land use for the last 300 years.

 

Nick samples the bog water for its isotopic composition. This is work done in collaboration with isotope geologists at the University of Cincinnati.

Post originally published on the Wooster Geologists blog.