TAHLEQUAH – As part of Libraries Celebrate the Earth Week, a university community in Northeastern Oklahoma had a chance to learn about a type of "cookie" that doesn't come fresh from the oven.
Students, groundskeepers, and faculty met at the Northeastern State University greenhouse this week to learn about trees in preparation for Arbor Day. They were told that "cookies" are the lowest crosscut sections of a tree. They are taken when trees are cut down, and they are used both for decoration and for science.
A proper "cookie" is cut without major gaps or holes, which allows researchers to best understand the history of the tree.
A few months ago, Michael Jefferson, NSU groundskeeper, decided to collect "cookies" from trees that were cut down for various reasons. At the moment, he has 10, and three of them were on display at the greenhouse. Another three are on exhibit at the John Vaughan Library.
"A lot of times, people use them for decoration," said Jefferson. "They actually preserve them for centerpieces and displays. We're more thinking of the historic value of them, as well as allowing the students to study them."
One particular tree cookie came from an American elm tree that stood where the outdoor basketball courts
are located, outside of the NSU Fitness Center. The elm was healthy, but it had to be cut down to make room for the athletic project.
The "cookie" is shaped like a heart, and Jefferson is not sure why, but he guesses the healthy tree had healed from sickness and grew around a diseased section.
"It's interesting that the tree from the outside looked very healthy," said Jefferson. "It was an American elm and stood perfectly straight. This was at the lower portion of the tree. I would suggest it was diseased, and it was able to heal and seal itself up. It looks like just another tree. It is a bit of a quandary."
After the cross section of the tree is cut, "cookies" are sanded down, using an electric belt sander for 10 hours. After that, Jefferson and others have used finer sandpaper to smooth the surface by hand.
"You sand it down with different grades of sandpaper," he said. "If you really want to study the tree, you have to use manual sandpaper to count the rings using a magnifying glass."
Christine Hallman, NSU associate professor of geography, took time to sand down a post oak "cookie" with grit No. 320 sandpaper.
"And so, you can see the rings are a little clearer," said Hallman. "I can see the rings, which are big and fat on the inside. Toward the outside, they are more narrow."
By examining the rings, scientists can discover evidence from the past, including years of rain, and years of drought.
"They record historical events and processes," said Hallman. "This one has a piece of metal in it. It's a fence. We call them a round of barbed wire, or the nail that goes around it."
The location of the metal can tell the scientist when a fence was put up, or when it stood.
"It is important because it can tell us about the campus' past and its history. It's also good for education. Students can see that trees are really great recorders," she said.
Jory Allison is a summer youth worker with Cherokee Nation who serves as a groundskeeper at NSU. He has assisted with the "cookies" by transporting them, and he said the rings are important because they inform the public about ecological history.
"For one thing, there's educational value. I think it's very important to learn about the very things in our world, just like anything else, and learning what the trees are around can not only help us take better care of them, but it can also open our perspective on the world," he said.