BOULDER -- There's a dying legacy in Boulder that University of Colorado (CU) researchers and students are trying to save: apple trees.

The Boulder Apple Tree Project began in the fall of 2017, but the collection of apple tree samples just resumed this spring.

CU Boulder said apple orchards used to be a common sight across Boulder back in the late 1800s. Many of them have died because of disease and drought, but many of the old trees are still scattered throughout town.

"In my backyard actually, there was this old apple tree and I was shocked in Colorado there was apples and so I started just looking into it," said the project's lead researcher, Katharine Suding.

Suding is a professor in CU Boulder's Ecology and Evolutionary Biology Department who came to the university from Berkeley, California.

She wanted to learn more about the trees, and their history in Boulder and Colorado.

"I'm an ecologist, and I'm interested in restoration," she said. "I was surprised that we hardly knew anything about these old apple trees that are dotted all over Boulder, Fort Collins, Denver."

So the first move was mapping.

CU Boulder undergraduates are locating and mapping all the apple trees along the Front Range, with the help of the community, to create an apple tree database.

"We have a way that people can submit information about their historic apple trees, or their trees that they would like to learn more about," Suding said.

The next step is learning more about the natural and cultural history of the trees.

"We really do need to do the genetic analyses to see if these trees have a historical lineage or whether they are probably unmatched to any known cultivar and likely from seed dispersed, kind of accidentally," said Suding.

Some of the trees may be the last of their kind. The life expectancy for an untended apple tree is only around 100 years, meaning that many may be close to their end already.

"I think that we have a limited opportunity to save these trees, a lot of them aren't maintained, they are on these old homestead locations in the middle of open fields - it is amazing that they are living this long," Suding added. "They are really old, they are all gnarly, they are falling over, they are hollow inside - they've lived a long, long time."

Researchers and students are taking samples of the apple trees and grafting them onto new stock in an effort to preserve them.

The ultimate goal is to create an urban orchard to plant the trees, use them as teaching laboratories for CU Boulder students, and preserve the history of the apple trees in Boulder.

"We're using this project as both a research project because it's good to find out about these trees, how they survived the last century in this environment," Suding said. "Also though, we are using it as a research opportunity for undergrads so there's a lot of educational benefits from involving students that are studying in Boulder to be able to go out, conduct research that's very local, but also really relevant."