Iconic photo by Joe Rosenthal showing the raising of the United States flag over Iwo Jima.

Trees have birthdays too, and scientists find out when they are by studying tree rings. This week on The Children’s Hour, we learn how to date trees, using dendrochronology with Dr. Peter M. Brown from Rocky Mountain Tree Ring Research, which maintains a list of the world’s oldest living trees.

This episode comes with a hands-on Learn-Along guide which meets and cites US educational content standards for use in the classroom.

Dr. Peter M. Brown takes core samples from trees to analyze their age, but we learn much more than that when we study its rings. Scientists can tell a lot about climate, fires, and even human or animal scarring. Tree Rings are nature’s notebooks, documenting the events of the years and storing that information in the libraries of their trunks.

Some trees are older than others, yet do not look as old as they really are. Bristlecone pines are the oldest trees on record, dating back more than 5000 years. But in another episode of The Children’s Hour called Forests, we learn that some seemingly small creasote “bushes” are actually more than 10,000 year old trees. 

That’s a photo of a bristlecone pine tree, located in the southwestern deserts of the United States. Learn a lot more about dendrochronology in our Learn-Along Guide that meets and cites US National education standards. Our Learn-Along guide includes even more information, links, and activities to better understand dendrochronology.

This episode was produced by Katie Stone, our Executive Producer and our Senior Producer, Christina Stella, with live engineering by Chad Scheer. Our Learn-Along Guides are written by Jonathan Dunski. Many thanks to Dr. Peter M. Brown for providing so many additional resources for us to share with our listeners.

©2023 The Children’s Hour Inc.

Playlist: Dating Trees

The Old TreeRound MountainTruth and Darkness
Happy Birthday, Trees!Brady Rymer and the Little Band That CouldHappy Birthday, Trees! - Single
This Old TreeTanya SavoryWhere We Live
Old Oak TreeKid KaleidoscopeThe Adventures of Kid Kaleidoscope
Count Your RingsBilly Kelly & Molly LedfordTrees
Great Grandmother TreeThe Okee Dokee BrothersWinterland
Little TreeLevity BeetLittle Tree - Single
Bossa In My HeartSergeQuadrado
Lemon TreePeter, Paul & MaryThe Very Best of Peter, Paul and Mary
Grandfather TreeClaudia Robin GunnSing Through The Year - A Little Wild Childhood
Steppin' InPodington BearThe Box Set
TreesGreen Chili Jam BandMagic Bike
The Old Oak TreeFarmer JasonRockin' in the Forest With Farmer Jason

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