The tree stands about 70 feet tall, and it's scheduled to be removed on Monday, so many are gathering to say goodbye.
[Ads /]
The long storied life of this bur oak tree in the heart of the Lincoln Park Zoo dates back anywhere from 250 to 300 years.
SEE ALSO: Lincoln Park Zoo news: All 3 new lion cubs are boys, veterinarians say
It pre-dates the founding of Chicago.
"The tree itself has lived through significant events, including the Chicago fire, so it's pretty amazing that it's still here," said Katrina Quint, the director of horticulture at the Lincoln Park Zoo.
Despite years of loving care from the horticultural staff, the mighty oak has reached its natural end of life.
ALSO SEE: Arbor Day: Here's how climate change can impact trees
[Ads /]
It's scheduled to be removed on Monday as a safety measure, because its heavy canopy branches reach over public pathways.
"We here at Lincoln Park Zoo have done everything we can to possibly save this tree," Quint said. "Considering that it is 80% dead, it's now a safety risk for it to keep standing."
Today staff was on hand to give tours, tell the bur oak's story and help zoo guests say goodbye.
People were able to write thank you notes to the tree, acknowledging its life and legacy.
Giana Demichael writing "thanks for always being there for us."
"It's gorgeous and beautiful and they did so well to preserve it having a life span that long," said Demichael.
[Ads /]
This remarkable and distinguished zoo resident has left its mark.
"It's sad but you know nothing lives forever and we're gonna make good use of this in a lot of different ways," said Judy Keller, a Lincoln Park Zoo Board member.
RELATED: Chicago tree canopy needs improvement; communities connect to plant and you can too
The tree will be used for different projects at the zoo.
"It will be made into art. We'll be doing interpretation with some of the wood," Quint said. "We'll use it for children's play areas here at the zoo. "
Parts of the bur oak will live on. The zoo has been working with the Morton Arboretum to preserve the genetics and create a new generation of oak trees.