The Sequel We've All Been Pining For
Trees in Lawrence just keep getting more interesting, and like the creators of the Rocky movie franchise, LPL's arborist-turned-librarian Jake Vail and I keep cranking out sequels to our virtual tours of interesting trees around town. If Rocky movies taught us one thing, it's that having a guest star helps, and since the stars of Rocky III and IV, Mr. T and Dolph Lundgren, don't seem to know much about trees, we've brought in someone else. Elizabeth "EJ" Jamison is the Kansas Forest Service's District Forester for northeast Kansas and gave a great tree-related talk and tour at the library earlier this summer. She did a little tree watching around town with us, too, so without further ado, cue the Rocky theme song (we don't have our own yet, and that one's hard to beat, anyway). Let's look at some interesting trees.
Tree #1: American Elm (Ulmus americana), map
Dan Coleman
Growing up in Kansas with parents who came of age in the 1950’s, I heard a lot about elm trees. This was odd, because whenever they pointed out locations, I couldn’t see any. Along with their elegiac descriptions came the story of an ecological disaster, Dutch elm disease, caused by fungi accidentally introduced to North America in the early 20th century, and spread by the elm bark beetle, a creature who loved those trees far more than my parents did, but which ironically destroyed most of them.
For a tree that is hardly there, we still hear a lot of references to the elm. Almost every town has an Elm Street, and most people know the horror movies set on one. The tree appears in countless books, movies, and plays, from Eugene O’Neill’s breathlessly titled Desire Under the Elms, to my favorite novel of last year, The North Woods, by Daniel Mason, in which he writes extensively about elms, including an elm bark beetle sex scene written so well it made me blush.
I’ve heard from people who remember that elms once lined Jayhawk Boulevard, forming a tunnel of luxuriant shade all the way across campus. They are hard to find now, but a few are still around. A pale comparison, the European white elm (sometimes called the Russian elm), is common, but once you experience the fuller, larger-leafed American elm, it’s easy to see the difference. One of the prettiest American elms in town is found near our Elm Street, although it’s in a place named after another tree, Walnut Park. You can see it looking north from the levee, just downstream from the Bowersock Dam.
When I look at this tree I wonder why these rare survivors seem quite healthy? Is Dutch elm disease still a threat, and these are just the lucky outliers, or can the American elm make a real comeback?
Jake Vail
Since on our Watson Park tree tour we were talking about a somewhat similar infestation here and now in Lawrence, that of emerald ash borers, I think I'll send your questions about elm disease survivors right to EJ. Something tells me our District Forester can handle it. But I have a few thoughts on other elmish matters.
I too recall my parents talking about American elms as street trees, in particular along E. Broad Street in Columbus, Ohio. Looking for a historical photo, I instead found one of those rare survivors you mention.
Then this, from the 1930s.
That's Columbus. I have to assume the canopies on either side are elms; certainly the vase shape of the first tree on the left says "elm." (Hang tight, there's more Ohio to come.)
Anyways, years later but still long before my introduction to arboriculture, I briefly volunteered at the Smithsonian Museum of Natural History, cataloguing little fossilized flying saucers. Or so it seemed, until I learned they were elm samarae (seeds, to most of us). Which tells us that elm seeds are wind-dispersed. Some time ago in our Interesting Trees series we discussed tree seed dispersal, and I mention it here because it's critically important to the elms, but mostly to contrast it with the next trees we're going to talk about.
Elizabeth "EJ" Jamison
Elm trees and Dutch elm disease (DED) is a loaded topic! Our North American elm trees are being destroyed by a fungus originally from Asia that is spread primarily by a European elm bark beetle. Complicated much?
Great question about the future of elms in the US, Dan. Many “sole survivor” American elms that avoided DED for many years have since succumbed to the disease. Additionally, many trees that were seemingly resistant showed no tolerance when inoculated. For those reasons, it’s thought that healthy American elms exist simply due to luck and random chance. But don’t lose all hope! Researchers have been able to identify American elms with some level of resistance as well as develop resistant hybrids. In fact, K-State’s John C. Pair Horticultural Center in Haysville, Kansas is involved with the National Elm Trial; a nation-wide effort to evaluate elm cultivars for DED resistance. The center has 18 cultivars of elm trees that show resistance to DED, and four of them are true American elms! So, although DED remains a significant threat to our elm trees, I’m not ready to give up on them.
Jake, it’s so cool that you catalogue fossilized elm seeds in addition to books! Elm samaras are some of my favorite tree seeds. They’re so cute!
Tree #2: Ohio buckeye (Aesculus glabra), map
Dan
One of my favorite tree places in town is Marvin Grove, just south of the Spencer Museum of Art on the campus of the University of Kansas. A small article on KU’s web site describes how then-Chancellor James Marvin led groups of students and faculty to plant trees here in the 1870’s, and more plantings followed until the area formerly known as North Hollow had become enough of a “grove” to be renamed as such in honor of Marvin.
The buckeye tree here, located near Richard Hollander’s welded steel I-70 sculpture, is clearly not that old. Surrounded by mature walnut trees, it reminds me of a college student among a group of professors. Buckeyes are mostly known for their seeds, which resemble the eyes of deer, and the tree is so closely associated with Ohio that the state’s flagship university has made the buckeye its mascot (Brutus the Buckeye is the only seed mascot I can think of). The range of Aesculus glabra actually extends from western Pennsylvania through Texas, and the trees are not uncommon in Kansas, where, in my childhood bedroom, a buckeye was almost always sitting somewhere on a desk or bookshelf, because they supposedly bring luck to those who possess them, and they are just a neat find.
Perhaps there is no one better to ask than Jake, an Ohio State grad himself, how such a connection of tree to state came to be?
Jake
Believe it or not, I'm not going to talk football. Much. Dan, Ohio certified arborist Mike Wilson has anticipated your questions.
First, one must recognize that in the 1700s what is now Ohio was mostly wooded. Lots of trees, lots of which were buckeyes. An early settler, Colonel Ebenezer Sproat, was nicknamed Buckeye by the Natives in the area, and it stuck. And spread. One must admit, the nuts have a certain appeal, as do the leaves and flowers. Ohioans in general soon were known as Buckeyes, and by 1840 presidential candidate and Ohioan William Henry Harrison chose the buckeye as his emblem. A hundred years later the state university was looking for a new mascot, a papier mache Brutus later appeared on the gridirons, and here we are. When I went to OSU freshman orientation, we were reminded that we were poisonous nuts.
New to Lawrence years ago, I was shocked when I found a buckeye tree near Lone Star Lake. I was again when I found one flowering in Lawrence Nature Park this spring. Good omens.
When my dad, also a Buckeye, passed, we found a shiny buckeye among his possessions. It now sits on my desk. I'd say my luck is generally good.
EJ
I’m proud to say that my undergraduate alma mater’s mascot is also a seed! Oakie the Acorn from the SUNY College of Environmental Science and Forestry. Unsurprisingly, we have a phenomenal timber sports team.
I most frequently see Ohio buckeye in bottomland riparian forests. I’ve come across groves of this small tree that seem to form their own mini forest under an overstory of trees like black walnut, hackberry, and American sycamore. These groves are stunning to walk through when buckeye is flowering. I’ve often wished that the nuts were edible because they look delicious, but alas they are toxic.
Tree #3: Horse chestnut (Aesculus hippocastanum), map
Dan
Dan: Horse chestnuts and buckeyes come from the same genus, and produce a similar-looking seed. If you’ve been a Lawrencian for any length of time, you have probably driven past one many times without knowing it, on the grounds of the old Carnegie Library, at 9th and Vermont (the tree is on the southwest corner of the front lawn). You may also have heard of a children’s game played with horse chestnuts called "conkers," especially if you’re a fan of British literature, for the game pops up in the work of Roald Dahl, D.H. Lawrence, and many others. I recently watched this video to educate myself how the game is played (any random 10 seconds should be quite enough to get the gist: each player runs a string through a horse chestnut seed, then takes turns using theirs to knock the other’s off its string).
Have you ever played conkers, Jake?
Jake
Well, it's like this. As mentioned, horse chestnuts and buckeyes are related. But horse chestnuts and chestnuts are not related. Chestnuts are a whole different thing. Horse chestnuts are Old World, and buckeyes are New World, and chestnuts are both. Such is arboricultural botanical nomenclature. This explains why Brits play and write about conkers (and no, I never have played), and Buckeyes play and scream about football. Go Bucks!
But back to the horse chestnut. I've witnessed first hand the fact that EJ is not only a tree expert, but a twig expert (get ready for a winter tree I.D. walk, folks!), so it's probably not news to her that horse chestnuts have horseshoe-shaped leaf scars, complete with nail holes. I plan to trot down to the Carnegie Library to investigate. Apparently horse chestnuts also are a favorite tree for bonsai, which I would love to see, especially in flower. And here's a nice summertime anecdote: Before refrigeration, German brewers used to dig cellars for lagering (cold conditioning). To protect the cellars from the summer heat, they planted horse chestnut trees, which have dense canopies and shallow roots. This led to modern beer gardens. Cheers!
EJ
Don’t even get me started on the arboricultural botanical nomenclature of “chestnut”. Anytime someone finds a tree with large, shiny nuts or toothed leaves they call it “chestnut” after the true chestnut (genus Castanea). That connection isn’t very helpful today because most folks have never even seen a true American chestnut since almost all the mature trees were tragically hit by chestnut blight.
Anyway, horse chestnut and Ohio buckeye can be hard to tell apart. One way to distinguish them is with the leaf scar trick that Jake mentioned. The leaf scars on horse chestnut twigs are more horseshoe shaped! The leaflets of these two species also have different shapes. Leaflets on horse chestnut are obovate, meaning oval shaped with the tip being wider than the base, while Ohio buckeye leaflets are elliptic with the widest part in the middle. Lastly, horse chestnut tends to grow larger than Ohio buckeye.
Tree #4: American sweetgum (Liquidambar styraciflua), map
Dan
If you’re a grouch around my house, there’s a good chance someone will ask why you’re being a “pokey seed ball.” This term found its way into our family lexicon when my kids were little and used it to refer to the fruit of an American sweetgum tree in the park where we often played. Everyone knows those green, pointy balls which hang from the tree and release flying seeds each fall, before falling to the ground, drying out and becoming as unpleasant as a hungry or overtired kid.
A yard full of dried sweetgum balls is no fun for humans, but a lot of animals like them. Finches enjoy the seeds within, as do a number of sparrow species, and yellow bellied sapsuckers. Squirrels and chipmunks wouldn’t turn them down at a potluck. But my favorite sweetgum-loving animal isn’t in it for the seeds. Pale green and mysterious as its name, the Luna moth often resides near sweetgum trees, the leaves of which its larvae love to eat. Luna moths can also be found at the center of a recent hit graphic novel for kids, The Moth Keeper, by K. O’Neill.
Their leaves may taste sweet to Luna moth larvae, but really, what’s with the name of this tree? Pokey seed balls aren’t sweet, and where is the “gum”?
Jake
I guess "pokey seed ball tree" is better than what I've been calling the "coronavirus tree." I mean, just look at those fruits. And people seem to dislike the sweetgum as much as they dislike the corona virus. Yet here it is, and it seems to be sticking around (so to speak).
Still, speaking of getting stuck, sweetgums are nicer than honey locusts.
But besides the nice fall colors, about the only nice thing the online hive mind has to say about it is "easy to climb." Which is true, and does count for something. And it gives me the opportunity to mention a new book, which I've failed to do so far. A few days ago I met a local — and female — arborist here in the library who strongly recommended Take to the Trees, by Marguerite Holloway. Which is about women's tree climbing. This is a big deal. When I worked as an arborist there was a grand total of one non-male arborist in the area (the Pacific Northwest, where there are hundreds of tree climbers), and she worked on my crew. Now it's a thing, and arboristas (I hope that's correct) are writing about it. Check it out.
By the way, the sweet gum is there, deep beneath the sweetgum bark. Probably not as sweet as tupelo honey, but I'll investigate.
Also, don't you think it's kinda cosmic that Luna (moon) moths eat star-shaped leaves?
EJ
Well, I’ll definitely be checking out Take to the Trees next time I’m at the library. I love a book about women in arboriculture and/or forestry!
I did not know about the relationship between Luna moths and sweetgum! Cosmic indeed. I believe Jake’s right. The common name (sweetgum) and Latin name (Liquidambar styraciflua) refer to the resin produced by this tree. I’ve read that it can be chewed as gum or for medicinal purposes, but I’ve never given it a try myself. Let me know how it is, Jake!
Although I love this tree for its wildlife benefits and beautiful fall colors, I have stumbled on its “pokey seed balls” while jogging around town more times than I care to admit. And yet I still find myself looking up at the leaves rather than down at my feet!
Tree #5, Black Tupelo (Nyssa sylvatica), map
Dan
Tupelo is a word I associate less with a tree than a town, Tupelo, Mississippi, the birthplace of Elvis. Another rock and roll reference, Van Morrison’s song, “Tupelo Honey,” also comes to mind. But the original tupelo was the tree, a native genus often found in the American south, known for its bright red fall foliage. We have some here in Lawrence, and a couple real beauties can be seen on the northeast corner of 8th and Mississippi and the northeast corner of 7th and Louisiana.
Some tree species, like this black tupelo, are real peacocks in the fall, while others don’t put on much of a show. I’ve never thought to wonder until now, but when we see bright colors on a mammal, bird, or insect, we can usually trace it to an evolutionary advantage. Is that the case with colorful deciduous tree species, and if so, how did their fall colors help them survive?
Jake
Now that sounds like a question for EJ. Positively Darwinian. I like it. My guess: fall leaf colors don't confer any evolutionary advantage. It boils down to physics, just a trick of light, more than biology. The colors indicate that the leaf and therefore tree are shutting down for the winter, so no advantage over or to other trees, no nutrients for other species (exception: fungi). Though it could conceivably benefit woodpeckers. EJ, change my mind.
So we've moved from sweetgum to sour gum, one of the tupelo's several common names. Its genus name, Nyssa, is the water nymph who raised Dionysus in Greek mythology. Who's probably at one of those horse chestnut shaded beer gardens right about now.
Unlike most of the previous trees we've discussed, elm excepted, the tupelo has dainty little flowers and fruits, famously favored by the bees (cue Van Morrison, please) and the birds, respectively. The fruits are especially loved by songbirds on their arduous fall migration south, fueling up before they cross the Gulf of Mexico, singing Van Morrison as they go.
EJ
In my opinion, black tupelo is one of the most underrated tree species in town. There are some beautiful black tupelo trees along the Burroughs Creek trail near 15th street that I walk by all the time. They look absolutely stunning in the fall! Take that, autumn blaze maple.
As a former Vermonter, I spend more time thinking about leaf color (and maple syrup) than the average person. Even so, it seems there are no easy answers when it comes to interesting questions about trees. In the fall, trees respond to longer nights by slowing and eventually stopping chlorophyll production (the pigment that makes leaves green). This allows carotenoids (the pigment responsible for oranges, yellows, and browns) to shine through. However, red and purple colors come from anthocyanin which is not typically present during the growing season and must be produced in the fall. So why produce a new pigment right before the dormant season?! Scientists are researching a wide variety of adaptive explanations including protection from cold temperatures, shielding from light, or deterring insect herbivory. Some trees turn red, some turn gold, some turn brown, some drop their leaves before they change color, some hold onto dead leaves through the winter. I could go on, but clearly there’s some interesting stuff going on as trees prepare for winter.
I did not know that the genus Nyssa came from a water nymph in Greek mythology, but it seems fitting considering black tupelo is often found in swamps. One of the coolest experiences I’ve ever had was seeing 500+ year old black tupelo trees growing in a wetland in Lincoln Mountain State Forest in upstate New York. What an incredible place at the far northern extent of black tupelo’s range in the US!
Dan
That's a wrap on this batch of interesting trees around Lawrence. Jake and I felt like we were a little long on the trees and short on the book recommendations this year, so we asked EJ if she'd share a list of some of her favorite tree-related books. Thanks again for joining the conversation with us, EJ, and here's hoping we see you at more tree-related programs at the library soon!
EJ's Top Ten Tree Books (in no particular order)
Black Woman in Green: Gloria Brown and the Unmarked Trail to Forest Service Leadership, by Gloria Brown and Donna Sinclair
Reading the Forested Landscape: A Natural History of New England, by Tom Wessels
The Last Wild Places of Kansas
—EJ Jamison is the Kansas Forest Service's District Forester for northeast Kansas. Jake Vail is an Information Services Assistant, and Dan Coleman is a Collection Development Librarian at Lawrence Public Library.
Photo credits: Dan Coleman (elm, elm seeds, buckeye, sweetgum, and horse chestnut trees); Jake Vail (buckeye seeds, buckeye blooms, sweetgum leaf and seed ball, black tupelo tree, black tupelo flowers). The photo of Broad St. in Columbus, Ohio, is in the public domain.
Branch out with the rest of Dan and Jake's ongoing Interesting Trees series.
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Interesting Trees (2018)
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More Interesting Trees (2021)
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Even More Interesting Trees (2023)
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Interesting Fruit Trees of Lawrence Public Library (2024)
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