This is my most favorite tree in the world. It may look small but it’s the biggest bur oak I know of. I’ve seen both the tallest and largest tree in the world but this is still my favorite. It’s easily over 300 years old. That trunk is about 3 feet wide and the span is probably around 80 feet. For perspective on how slow northern bur oaks grow, a branch from one of my smaller bur oaks got torn off 40 feet up during a storm. It was 11 inches wide and had 110 rings. The trunk of that tree is about 20 inches wide. That’s why it’s easy to see how this big tree is at least 300 years old! There’s not a person alive that has seen this tree in their lifetime as anything other than a mature, giant tree.
How did it survive? This was prairie when it was “born”. You wouldn’t have seen another tree around in this photo back then other than perhaps a cottonwood on the bank of the nearby creek. This is prairie land. The mighty bur oak has thick bark that can withstand the fires that prevented other trees from surviving, but it takes years to develop that thick of bark. It can survive severe drought with its deep taproot.
Perhaps the somewhat narrow steep valley that this creek cut has something to do with it. Could it have been much wetter ground 300 years ago that prevented the fire from burning the grass around the tree? Maybe the fire rarely went down into the valley. This could’ve gotten it to 30 years old where it could survive the fires.
What then of the bison? What few trees that would’ve been around were used heavily by the bison as scratching posts. Bison herds were very destructive at first glance. They’d eat the grass, chew up the dirt, and rub trees raw. But, the prairie needs that! The newly exposed dirt would bring forth wildflowers and other forbs. The bison eating the grass is what actually adds carbon to the soil by the plants trimming some roots after grazing and making new roots. Prairie grass roots go down deep, some over 10 feet. That’s what actually built up the soil, not the decay of old dying plants. Seems strange at first, but yes grazing grassland takes more carbon dioxide out of the air and puts it into the soil than just letting it grow wild does!
Quick side note just to prove the point more fully. Only 40 miles or so from here is Jeffers Petroglyphs. It’s an area where humans have been carving into the exposed rock for 7,000 years. The entire surrounding area is still intact prairie because it was impossible to till the soil with the large exposed rocks. On a tour I asked if they’ve ever dug down to find more rocks that used to be exposed. Sure enough they had recently dug down in an area and showed it to me. They started where the rock was exposed and followed it down its natural slant, deciding to quit about 3 feet down from the surrounding soil. All the rock they exposed had carvings on it! And that’s just were they decided to quit. That’s what prairie grazed by animals does, it builds the soil by adding carbon. That’s what makes our topsoil so black in the prairie states, the carbon from centuries of prairie grass roots. Experiments in the last 30 years has confirmed it.
Okay, back to the bison.
Perhaps the bison preferred the small river just a mile away that has a sandier bottom to drink from, or even the large Minnesota River 2 miles downstream to bathe in. We’ll never know.
What then of the Dakota that lived here in this tree’s early life? They used trees for various things but maybe not the bur oak. Either way, they let it stand.
Tornadoes, thunderstorms, and windstorms are a constant threat on the prairie for a tree that stands above the rest. I’m guessing it was protected in this 60 feet deep valley from the full force of the storms it’s seen.
Then what about when this tree was middle aged? When Europeans first settled the land and began to till the soil. Lumbar was very expensive. In fact most settlers, including my ancestors, lived in sod houses or caves before they could build a house. Even at 140 years old, this tree had enough lumber to build a small house at the time. Why wasn’t it cut down?
We’ll of course never know the answer. My hope and belief is this. That everyone that has ever seen this tree saw it in the same way that I did the first time I laid eyes on it. They saw the beauty. They saw the perfection. They saw that some things are worth more than money. They realized that this tree was more important than their current needs. Perhaps they even thought they’d like their great, great, great grandchildren to be able to have a picnic under it.
I’m so thankful!
Thankful for everything that others have done for me, both in my lifetime and before I was born. From people who know me, and from strangers alike.
Even those who had no idea that a decision they made would make me smile every time I run past this tree.