- This is one of the last remaining old-growth forests in the Eastern United States, and it's here in Western North Carolina.

Joyce Kilmer Memorial Forest is a 3,800-acre tract in the Nantahala National Forest, set aside in 1936 as a memorial to Joyce Kilmer, author of the poem "Trees," as in, "I think that I shall never see a poem lovely as a tree."

But what is an old-growth forest?

I met up with dendrologist Steph Jeffries in a different season and a different forest to find out.

- Old-growth forests are something that have captured human imaginations for years.

We think of these, especially Joyce Kilmer, as being like a kind of cathedral, but our idea of what old-growth means has changed over time.

In our human imagination, old-growth means that it reaches a point of equilibrium and then it never changes, but I think that's partly our human timeframe and lifetime.

Some of the oldest trees at Joyce Kilmer have been there for over 400 years, but there have been a lot of changes to that forest.

These are still dynamic forests, just not really in our human lifetime timescales that we are used to operating in.

- The presence of the massive tulip poplars at Joyce Kilmer are actually a clue to the forest's dynamic past.

- Tulip trees are unusual in that they need open sunlight and open canopy to thrive, so when we think about Joyce Kilmer, something pulled down the forest that was there before and established those tulip trees and other species of trees 400 years ago, probably some large-scale disturbance like a tornado or massive storm.

Most trees either live fast and die young or they're slow-growing and live a long time.

Tulip tree is interesting because it has a lot of seeds and they grow very, very quickly in high-light conditions, but then they're able to persist and live for a long time.

- Is that why they grow so straight?

'Cause they grow fast?

- Yeah, they're like, "I'm gonna win."

Yeah.

- Joyce Kilmer is an old-growth forest, partially because it wasn't logged in the early 1920s, like much of its surroundings.

- The timber companies kept changing hands, so it was put off a little bit.

There's a romantic story out there that even the loggers didn't want to harvest that amazing tract of old-growth trees.

Maybe that's true.

I'm sure there were people who felt that way, but in that area, there were deposits of bauxite, which is the kind of ore that is used to make aluminum, and that took precedence, and so Lake Santila was created to be a source of hydroelectric power.

Well, that cut off the rail lines from that tract that is Joyce Kilmer today.

And so that delayed things even further until the 1929 stock market crash, and the lumber company that owned that tract of land went bankrupt, and then shortly thereafter, the Forest Service purchased that tract of land.

They were actually looking for an old-growth tract of land to honor Joyce Kilmer, who was the poet laureate who was killed in World War I.

- Its location shaped the type of forest it is and further protected it from disturbance.

- Joyce Kilmer is a rich cove hardwood forest.

The forest is tucked underneath the Great Smoky Mountains, which gives it some protection, and the forest is kind of actually down low, even though it's in Western North Carolina, about 2,200 feet.

If you walk around Joyce Kilmer, you can see that it's in this kind of protected bowl.

That bowl enables it to avoid things like large storms, so wind throw is not as much of an issue there.

The forest type is really moist, so it's not susceptible to fire, and so that has enabled this particular forest tract to remain intact since it was protected from logging for a very long time.

- And lack of disturbance means the forest has been able to develop and diversify.

- Joyce Kilmer is especially diverse.

It has many species of trees in the canopy, the saplings, and mid-story, very diverse.

There's not any one type of tree that is dominant over the rest.

The forest floor, because it's had all that time and hasn't had a lot of soil disturbance from logging or other things, has remained intact, and it's incredibly diverse.

♪ it's incredibly diverse.

♪ - Joyce Kilmer is surrounded by undeveloped land, but you don't necessarily have to go somewhere rural to find older trees.

You'd be surprised what you can find tucked into more developed areas.

We visited the Piedmont Nature Trails at the North Carolina Botanical Garden in Chapel Hill to check out some pretty big tulip poplars there.

This is a specific type of forest.

What is this forest called?

- This is a bottomland hardwood forest that we're standing in here, which is in the Piedmont.

We're adjacent to a creek.

The creek will overflood seasonally.

When it floods, it carries with it sediment that then is deposited on these kind of flat areas that we're standing in, and these make for really nutrient-rich soils.

They stay really moist.

They're pretty deep soils, and so those are great conditions for trees like tulip tree and then some of the other hardwoods that are in the surrounding area.

It's not just tulip tree.

There's a pretty nice diversity of plants, and then shifting from the canopy down to the forest floor, this forest floor is also very diverse.

It's early in the season where we are today, but it will have this really nice carpets of wildflowers.

It's very reminiscent of Joyce Kilmer, which also has similar tree species like tulip toddler, although they're a giant, and then a really rich wildflower understory, so it looks similar in terms of what's living here.

- We headed to a patch of forest on UNC Chapel Hill's campus around a mile away along that same creek to visit some other very old trees.

We're in the middle of UNC's campus right by the baseball stadium.

- Oh, my gosh.

- This is the coca pinetum, and we've got some very, very big trees.

- That's an impressive tulip tree right here in the middle of campus.

- It's surprising.

- And it's got an interesting sharp bend up at the top.

Something must have happened at some point.

- Yeah, something might have fallen on top of it and broken the crown out.

- But this is big.

This is bigger than the ones we were just at.

- It is, yeah.

- It's not quite Joyce Kilmer's size, but this is impressive.

- Not quite, but probably it'd be more than one person to put their arms around it, so.

And here it is.

It's still resilient.

- Just right here, right?

We just walked 500 feet from a parking lot.

- Continuing down the trail, we found more evidence that this patch of forest has been here for a long time.

- I see another big one.

Very cool.

- This is a pretty old tree.

- Yeah.

- You know, I think it's interesting, like this area where we're standing is pretty sloped, so it's pretty different from both that bowl-shaped Joyce Kilmer and the Piedmont Nature Trails, which were kind of flat.

But there must be, you know, there must've been an opening here where the seeds established.

Sometimes trees grow in places we're not really expecting, like nobody tells the tree, like, "Well, this isn't the right forest type for you."

The seedling can be successful if it's got good soil and open sunlight.

You know, here it is, living its best tulip tree life.

- Yeah, it certainly doesn't look like it's struggling.

It looks very happy.

- Yeah, it's kind of special that it's found a little spot right here on campus.

With her knowledge of trees, Steph is able to look at the forest around us and see other clues about its age.

I mean, this is a large American beech.

They grow pretty slowly.

Same thing with the hickory, with that braided bark.

- Oh, yeah, right there.

- And of course, more huge tulip poplars with branches the size of trees themselves.

- So the tulip trees are big and they grow quickly, but it's likely that some of the other trees are just as old here.

They just are slower growers.

So the hickories and the beech trees.

- Yeah, it's kind of nice because the tulip trees make us stop and pay attention.

And then when you start to look around more, you're like, "Oh my God, "actually there's so much cool stuff around them."

- Oh, yeah, yeah.

I mean, these are old trees and those are definitely the stars of the show.

- Yeah.

- They get your attention.

- If you enjoyed that story, there's more where that came from.

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