
A yellowwood narrowly avoided Louisville’s 1974 catastrophic tornado that devastated portions of nearby Olmsted-designed Cherokee Park and toppled trees in our part of town. The tree is big for a yellowwood (Cladrastis kentuckea). Not state champion big, but certainly exceptional by any measure, even in its weakened condition. Multi-trunks have hollowed out cavities, and its upper limbs are cabled together to prevent further splitting. Top Hill’s many beautiful trees attracted Sharon Lamb to the neighborhood in 1999, and she has been admiring and caring for her yellowwood since. The yellowwood is slightly taller than her two-story house and has a circumference, at slightly below chest height (knobby from old branches), of ten feet, five inches.
“Ed has joked with the tree guys about my ‘sacred’ tree. They couldn’t believe I would repeatedly pay them to trim it for balance and replace any of four cables that would be yanked out in a storm.”

Ed Garber and Sharon Lamb—friends, partners and yellowwood lovers.
There is little not to like
Mike Dirr, American maestro of all things woody, wrote positively about yellowwood in his Manual of Woody Landscape Plants:
“Excellent tree for flowers and foliage; the medium size and spreading habit make it a choice shade tree for smaller properties; can be used as a single specimen or in groupings; surprisingly beautiful yellow fall color and winter bark.” And despite its southeastern USA provenance, yellowwood is hardy to -20F (-29C) and adaptable to acidic soil. Yellowwood develops a rounded canopy and is suited for smaller yards and for planting under powerlines.
Julian Campbell, my go-to botanist, said native stands of yellowwood are hard to find and harder to reach. In the Bluegrass region of central Kentucky, they are found on the towering limestone Palisades overlooking the Kentucky River. There are also scattered populations in McCreary and Whitley Counties in Eastern Kentucky, where they are growing in shale-base soils, rich with calcium. These trees are found as well on bluffs of the Mississippi River in well-drained, base-rich Loess soils.

Heartwood and a stroke of luck
Paul Cappiello, Executive Director, at Yew Dell Botanical Gardens in Crestwood, Kentucky, said he’s turned wood with the heartwood.
“It’s fabulous when worked fresh, but the wood fades quickly. Still a nice wood when cured but not canary yellow. Don’t find it very often. It is delightful to carve but is prone to checking if you don’t stay on top of it. I’ve worked late into the night to quickly remove as much wood to fight the checking.”
Perhaps it was a stroke of luck that the neighborhood’s yellowwood was planted on Top Hill Road on top of a thick layer of Ordovician limestone, hundreds of millions of years old. Our local limestone is distinguished by sinkholes and caves—Mammoth Cave being the most famous example.
The yellowwood took to a remarkably friendly and sociable neighborhood. We mourn deaths and welcome new babies.
Later this month, Rose and I will host a wine and cheese party with our neighbors. Gatherings are common throughout the summer.
Plants have social lives in our neighborhood too
The origin of the tree has puzzled me for 30 years. I first suspected the yellowwood, one of America’s most uncommon trees in the wild, might have been there long before the neighborhood was developed, beginning in the 1920s. I called John Swintosky. (I would argue there is no landscape architect with a comparable working knowledge of woody trees and shrubs.) He looked at the tree appreciatively, turned to me, smiled and said the tree was planted by someone with good taste. We both love the tree, and we’re not alone, but the yellowwood had not preexisted the construction of the house. But still, 100 years of surviving a tornado, ice storms, droughts, and lawnmowers is noteworthy.

Sharon’s neighborhood yellowwood was in full bloom last month
I walked down the street to see the white, pendant “wisteria-like blooms” five doors away and met Oliver Roe halfway there. He was gardening near a large American beech with lily-of-the-valley covering the ground underneath. (Note to self: Don’t ever plant lily-of-the valley pips in good soil again. They only sulk. Though slow to increase, they clearly thrive in unenriched soil with root competition.)
I told Oliver I was going to see the yellowwood. He and his young family moved into the neighborhood last year and had already discovered the tree. He told me that Todd Korfhage had been by for a landscape consultation earlier in the week and had mentioned the yellowwood. I called Todd the next week. The Korfhage family are nursery and floral royalty in Louisville, They’ve been in the nursery and floral trade since 1919. Todd remembered the yellowwood from his teen years. “The tree was already big,” he said. His father worked on the property in the 1970s and 1980s.
Yellowwood peculiarities
Flowering is better some years than others. Paul Cappiello said. “Flowering can be a bit cranky and somewhat unpredictable. Not sure I buy the alternate year advice that is often presented. I don’t think it is that consistent.” Yellowwood trees in Salvisa had no flowers this year. The same was true for an approximately 60-year-old beautiful tree on Mac Reid and Tay Breene’s farm, one mile from ours.

Yellowwood blooms. Scott Beuerlein photo.
“It could be due to the predator satiation hypothesis,” Julian Campbell told me over the phone. “If some plants produce an abundance of seed, populations of prey build up, reducing the likelihood of being overwhelmed by predators.” Oaks are an example where there is the occasional explosive “mast season” with an abundance of acorns, and then several intervening years of scarcity.
Fragrance is an often-mentioned bonus. Blooms on the neighborhood tree were too high for me to photograph or to catch a scent. I don’t have a good nose for scent anyway. Sharon Lamb said, “The scent is sweet, subtle. When you walk up on the porch, there’s a moment of being enveloped in a heavenly cloud, but it’s not overwhelming. It’s hard to describe a scent.”
Joanne Fischer of Weaverville, North Carolina, formerly from Louisville, has made a life in gardening. She said, “I don’t remember it knocking my socks off.”
Why the yellowwood discrepancy?
Thousands of flower fragrances exist in nature, some affected by time of day, bloom stage, climate or soil. Or perhaps it is friendly fungi. Zoe Schlanger, in The Light Eaters, mentioned an interesting possibility. “…aromatics in patchouli and the antioxidant power of artichoke heads have all been found to increase with the presence of certain fungal associations…The list goes on and on. Where a plant ends and fungi begin becomes hard to parse…By some scholars’ accounts, roots are literally the product of fungal influence, made to stitch plants and fungi into relation.”

Our neighborhood yellowwood
Life goes on
Seed distribution of yellowwood relies principally on gravity, but it is possible that seeds are cache for small rodents—mice and squirrels. There are several yellowwood seedlings under Sharon’s tree on north facing hillside, adjacent to the road. I’ve often thought I should ask for one. Maybe trade something from our garden. ( Ed Garber, Sharon’s friend and partner, has free rights to all the Lenten rose seedlings he wants.)

My yellowwwod seedling. There and gone.
Two weeks ago, ten feet from our front sidewalk, in a bed of Lenten roses, I saw a yellowwood seedling, maybe a year old. Heaven sent? The seed sower, I suspect, was a chipmunk. Our garden was periodically a happy hunting ground for neighborhood cats, but there have been no cat sightings at the pond for several years. Our chipmunk population exploded.
The tree whip vanished within a week. No sign of grazing or foul play. Simply gone. There is no certainty, only hope, when you mind a tree seedling. Still, I was sad. I never had the chance to touch the little tree.
Sharon offered me another chance.
Not only would she be happy to share a yellowwood for the street, but she offered another one for the farm in Salvisa.
Loved this, Allen! And that you checked with all the experts to get a full picture of Yellowwood life!
Thank you, Mary. We’re lucky to have our local experts
I am entranced by them. My next door neighbor planted one in her front yard. I suspect it will prove to be a poor choice for our small suburban plots: it’s planted on one half of the front lawn between the walkway and driveway. The entire width of our plots is only 50 feet!
Susan, I think your neighbor will be fine with the yellowwood for years to come. Maybe a little tip pruning ten years from now.
Good to know! Thank you.
Traveling in the Philadelphia area for a week of garden tours, I was at once immersed in post-Revolutionary War gardening, being regaled by the guide/reenactor at Bartram’s Garden who pointed out the handsome Cladastris specimen there multiple times from various angles, so often that I felt obliged to photograph it each time he mentioned the tree. And the very next day it got better at Meadowbrook Farm where theirs was covered in even more blooms. Coming from the PNW where we are not typically allowed such a floriferous display, when we find Cladastris at all, I thought it was a real treat.
Tia, thanks for the Philly tour. I hope you got to Chanticleer. They’ve got some nice yellowwoods too. We just got back from the PNW (Bellingham, WA). No shortage of late spring blooms there. I’ve never seen so many Chinese dogwoods. Loads of white-flowering angelicas along the roadsides.
Oh, those blooms. Oo la la. Very much enjoyed learning about the yellowwood tree. Felt like I was walking around the tree with you. Hopefully I will be some time. Still waiting on a gameplan for the gimpy knee.
Thank you, Jenny. Will have to show you the yellowwood sometime. Wishing you a return to a happy knee very soon.
Not sure what possessed me, but I planted one about a decade ago at home in western Montana. There are a few on the University of Montana campus, so we knew it was cold hardy. Ours bloomed once; two panicles, hidden in the foliage, their presence only detected in autumn after initial leaf drop. It’s also had an unpredictable tendency to shed living branches during minor wind events (nowhere close to tornado-force winds). But ours is a lot of disfigured trees, so it has plenty of company.
Michael, I admire your sense of adventure. I couldn’t imagine a yellowwood in Montana. That yours has hung on for ten years is remarkable. I wish I could grow a grove of quaking aspens…
Hi Tia,
Nice story. Wondering if you have read the book “Founding Gardeners?”
It’s a gem, both historically and botanically.
Well worth the read, if you haven’t already.
Washington, DC has been experimenting with a variety of species to replace the Norway maples, oaks, and ginkgos that were commonly planted as street trees decades ago, and are now failing or just too big. I was very pleased to see a yellowwood appear on my block a few years ago. The flowers are beautiful, and sweetly fragrant without being cloying. In addition to their smaller size, they don’t produce massive amounts of pollen in the spring, and don’t drop messy or stinky fruit all over the sidewalks and roads in the fall.
John, interesting yellowwood info about the smaller pollen production.That should please many folks. Do you like the other smaller tree selections being planted in D.C.?
I have been a bit confused about Cladrastis Iutea and Gymnocladus dioica. In my area, Virginia, USA the people from Bartlett’s, the major go to tree people (I understand they take care of the Queen’s trees…King’s trees now I suspect) they refer to the Yellow Wood, Cladrastis as Kentucky Coffee which is listed in my Smithsonian Tree Book under Gynmoclaudus. They both do belong to the Family Leguminosae. I have a Cladrastis lutea that came with a tag. When I asked Bartlett about siting it within my property which has all the various situations one could hope to have, the gentleman said, “Oh, yes, the Kentucky Coffee! Hmmm, I thought, I had seen a really huge one on the campus of the University of Virginia in Charlottesville and the guide had said it was Gynmoclaudus. Dioica. (Said to be over 100 years old.) Would love it, Allen, if you could explain this to me. The leaf structures are definitely different so I can identify mine as one or the other but wonder how the ‘Kentucky Coffee’ part has become estranged.
Letitia, someone is playing loose with common names. There are bluebells, and then there are bluebells. For instance: Virginia, Scottish, English and Spanish. All different. Don’t be confused. In your case, stick with the Latin names. I presume your tagged Cladrastris is the real deal—-yellowwood and not Kentucky coffee tree. Yes, they are both legumes, and native to Kentucky, but with different distinguishing features and growth characteristics. I love both trees! Here’s a link to 2013 Garden Rant story I wrote about the Kentucky coffee tree. https://gardenrant.com/2013/04/pour-me-another-kentucky-coffeetree.html
Thanks Allen. Very helpful. My tree has the single leaf at the end of the spray so am sure it is lutea