Local trees with confusingly similar leaves

Most every street and alley in St. Louis has one or more (or all) of these trees. There are other trees around with similar leaves, but these four were difficult for me to distinguish once upon a time. Identifications can be fairly easy if a tree is in flower or fruiting. Many people can instantly identify a walnut nut or a sumac berry cluster, but fruits and nuts are usually on the trees for a limited time. For most of the year, we have only leaves and bark to help us make identifications. Bark can be really tricky (it all looks alike at first), so I'm discussing only the leaves here. 

This picture shows one leaf each from (left to right): tree of heaven, smooth sumac, golden rain tree, and black walnut.  

One leaf each? Yes, these leaves are pinnately compound, meaning each leaf is made of a central stalk with a row of small leaflets attached to each side. This can be confusing, but leaves sprout out of the buds that are arranged along a tree's twigs or its stem. The growth that comes out of the bud is the leaf, whether it is a simple leaf like an oak or a maple, or whether it is a compound leaf like these. Another way to say it is that the bud is located at the base of the leaf, and for these compound leaves, the bud is located at the base of that central stalk, and not at the base of each leaflet. However, I'm not a botanical authority so somebody might disagree with my explanation. Anyway, after a while you get used to distinguishing between them and you don't worry about it that much any more!

Many sources will tell you how many leaflets are found on each leaf of these four species and how large each leaf should be. Guess what? There is not one number or one size for each tree. There are ranges, and the ranges overlap -- perhaps not the most helpful markers for making a casual ID. Some sources will tell you that the leaf of one species always ends in a pair of leaflets while some other species ends in a single leaflet. I don't think these trees read botany books -- or maybe they just don't care to obey botanists. In any case, you might find a single or double leaflet at the tip of any of these, as I have.

Looking at the leaflet margin does help. The leaflets of tree of heaven (below, left) have a mostly smooth margin, with one or two larger bumps at the base. Walnut leaflets (below, right) are also smooth, but do not have those bumps, and the curve continues smoothly, uninterrupted right to the base of the leaflet. 

Both of these leaflets can feel slightly fuzzy, but I think the walnut feels fuzzier sometimes. In the right light you can sometimes see tiny sparkles on the topsides of walnut leaves. Something very small there reflects the light (seen as tiny white dots on the leaflet below). I also find that the little tips of walnut leaflets are longer than on the other species here. The tips are drawn out to a longer, narrower point. 

Leaflet margins are serrate for the smooth sumac and the golden rain tree, but leaflets of the golden rain tree (below, left) seem to me to be more dramatically serrated, more complex, and the little veins are more pronounced than for the smooth sumac (below, right). The serrations on the smooth sumac leaflets are more orderly, repeating like uniform little stairs. If children were cutting these leaves out of construction paper, the kids cutting out the golden rain tree leaflets might being paying less attention, perhaps going a bit more free form. The smooth sumac cutters would be sitting upright, like ramrods, occasionally glancing at their compatriots with mild disapproval. 

While I find that individual leaves of these four species overlap in size, the leaves of golden rain tree are usually noticeably smaller than the others. They are especially smaller than leaves of smooth sumac and tree of heaven. 

The two that were most difficult for me to learn to distinguish were tree of heaven and smooth sumac. The stems and trunks look a bit similar, and young tree of heaven individuals can be similar in size and shape of canopy compared with smooth sumac.  I've noticed in St. Louis that they sometimes grow up together in the same places. As noted above, the serrated margin of the smooth sumac sets it apart. It may be helpful to look at the leaves from their reverse side, especially if you think you have both species present and can't decide which is which. I'm always surprised at how light the underside of the smooth sumac is, almost white sometimes. 

Some use the scent of the crushed leaf as a distinguishing factor, holding that the tree of heaven has a strong and unpleasant smell. They both stink to me.

Below, left to right: underside of tree of heaven, smooth sumac, golden rain tree, black walnut

Shortcut: although fruits and nuts are not on the trees for long, look around in the leaf litter (or amongst the fast food wrappers and beer cans) at the base of the tree. Walnuts turn black and stay on the ground for a year or more. Golden rain trees have little papery brown capsules that last for months. The reddish berry clusters of smooth sumac harden and turn brown, and some will fall to the ground. If you find any of these you know the parent tree is probably just over your head. Tree of heaven produces little wind-blown paper samaras, so if you're poking around under those trees for off-season clues you're out of luck.

Gardening in the pandemic

I'll bet a lot of people will have fantastic gardens this summer. With all the commute time I have been saving every day, I'm getting more gardening done than I have in any of the past 15 years. So far we have planted about 70 trees and shrubs in the highway forest and have managed to keep them all watered in daily on a regular schedule.

Magnolia "Genie"

In the front yard, I planted a magnolia, two hydrangeas, a coralberry shrub, and several ferns and woodland perennials. The magnolia tree has begun to bloom. It is a Magnolia 'Genie', a spring/summer rebloomer with incredibly deep wine red blossoms. Really striking.

I had in mind to dig a small pond for that area but when I started digging the hole for the magnolia, I discovered an old concrete basin just under the grass. It still holds water, so I cleaned it out and made some adjustments to my planting diagram to accommodate this stroke of luck. I recently got permission to bring some mossy old cave rocks home from the grounds of the convent where I work. I believe these were once part of a grotto, likely from the early 20th Century or maybe even earlier. After some trial and error placements, and lots of thought about Zen gardens and wabi sabi, I found just the right arrangement. Once the ferns and other plants fill in, the stones will be partially visible poking out here and there around the water. I could not be happier. By the end of this summer it is going to look absolutely fantastic!

The little island in the middle of the pond is a part of the basin and it looks like a big knob of concrete and old slag glass. When we moved here twenty years ago, there was a planter in this location made of concrete and cave rocks. It was about four feet tall and was shaped like a fountain, with a basin atop a central pillar. The basin was filled with soil and planted with sedums. It looked really old fashioned so we took it down, maybe with a sledgehammer? I don't really remember. Obviously, this little island in the center of my new pond was the base of that planter. The "planter" and the basin were actually a pond and fountain. I wonder if this garden feature is original to the house?

So now I've covered that little concrete and slag glass island with a thick layer of soil and a top coat of moss. I stuck a few wild ginger rhizomes in under the moss as well. The idea is a little mossy island with some wild ginger leaves hovering over the moss. It should add a lush note to the overall composition.

Nobody puts on a show like the redbuds. Our little highway right-of-way forest has become something spectacular each spring with swathes of redbuds and wild plums in bloom. Next spring they will be joined by the first blooms of white dogwoods. In a few years this strip of forgotten land will be the most gorgeous spring display anywhere in the neighborhood. 

The pawpaw trees are loaded with blossoms. Last year was the first year I saw fruit. Perhaps this will be a bumper crop. Maybe I'll even get to taste one! Getting these trees to survive here has been a real challenge. The soil is dry clay, no topsoil really, and it is packed hard. 

My first attempt was to transplant a couple of wild trees from the woods. That was a failure. It seemed like the trees died instantly. Next, I bought two small potted trees from Stark Brothers Nursery. They died in short order as well. The next year, I ordered 15 bare root trees from the Missouri Department of Conservation. That was a bit better, with most leafing out just after being planted. A few of them survived the summer. The following spring, I went back to the woods and dug some soil from a couple of different pawpaw groves, brought it home and worked it into the soil around the baby trees. My hope was that any symbiotic fungi or bacteria in the soil where trees were already thriving might help my baby trees survive. It seemed to help as all the trees that were still alive lived through the following summer. I have since lost one or two of those though. 

A few years ago I got four potted pawpaws from Forest Releaf and they are now five to seven feet tall and just beginning to spread branches out to about five feet. Yesterday I was weeding and found a new stem coming up a few feet away from the trees. Clearly, the pawpaws are beginning to colonize this area. 

And then more happiness this morning -- the first butterfly of the season, a swallowtail, was fluttering around in the grass and perennials near the pawpaw grove. Sleek and new, this little lady may be looking for a place to lay eggs soon. Pawpaw trees are a great host plant for swallowtail larvae. I hope she survives the songbirds long enough to reproduce.

Everything seems to be bursting out in bloom right now.The bluebells at the base of the big elm, clove currants and celandine poppies, fragrant sumac, mint weeds and ubiquitous wild violets. Missouri wild plums stand at the top of the hill draped in white, and Jack-in-the-pulpits peek out from beneath the arborvitae. It's just getting started. There's so much more to come.

Looking forward to another year of gardening

Another spring is here in Shaw and the rains have been very generous to us so far. We should have an excellent growing season as long as we do not see too much summer drought. The prairie plants at the Thurman Gateway Prairie are thriving and masses of flowers will begin appearing in a couple of weeks. Already we have seen the native clematis, the native geranium and prairie coreopsis flowering. Only about 60 species of flowers left to go! Prairie watchers know that once they get started we will continue to see flowers into November.

The Shaw Memorial Forest is growing as well. We have about 250 trees planted along the 3800 block of DeTonty so far. Through grants and donations we have procured another 300 trees this spring and that should finish the entire block and fill in a few holes where previously planted trees have died.

Our next planting day is Saturday, May 7th. We will meet at 9am at 39th Street and Detonty. Come with your shovels and garden gloves. You can find details of the planting day here or follow us on Facebook for updates.

On Saturday we will also hold a flower sale at the tree planting site. Flowering annuals and native perennials are $2-$5 each. Flowering trees are $10 each. After the tree planting we will hold a drawing for free trees as well.

New flowers at the prairie

The lovely Clematis virginiana is finally blooming at the prairie. This is the first time it has bloomed since we planted it three years ago. Good things come to those who wait!

Read all about this diminutive plant here.

native garden in Shaw

Volunteers from the neighborhood are busy this morning planting a couple hundred native flowers, grasses and trees on the highway right-of-way at DeTonty and 39th. this makes one more addition to our big plan for transforming the highway turfgrass into a variety of native gardens along the northern perimeter of the neighborhood. among the plants being installed is blue aster, Squaw flower, palm sedge and sassafras tree.

Howell Prairie

Yesterday I visited the cold and frozen Howell Prairie in Weldon Springs. I first heard of this prairie last week at the holiday party of the North American Butterfly Association. Apparently, the site was the location of a massive Superfund clean-up a few years ago. Now a 150-acre prairie has been planted as part of the ongoing management plan.

When I arrived I was immediately struck by two things. First, the site is dominated by an enormous white hill. This thing is huge. It is visible in nearly every photo I took. Second, the prairie is part of a federal installation and is owned and administered by the Department of Energy.  There are lots of signs around telling you what can and can’t be done. See their website here.

Check out St. Louis in this map!

There is a large, impressive interpretive center on site with displays about the history and current management of the land. Here is what I learned.

The prairie is new. It was created in the winter of 2003 and 2004. The site was seeded by DJM Ecological Services with about 80 species of grasses and forbs. Jon Wingo, the owner of DJM, is also the President of the Missouri Prairie Foundation. You can see a blurb about the Howell Prairie on the DJM website. Ongoing management includes both mowing and burning. According to a person I spoke with at the site, the public is not allowed to observe the annual burns.

One corner of the disposal cell

The prairie surrounds the site’s central feature, the huge white hill. This hill is actually an enormous tomb filled with toxic waste generated at the site in years past. The “disposal cell”, as they call it, was engineered to safely sequester the waste for 1,000 years.

The disposal cell is 75 feet tall and covers 45 acres. It contains 1.5 million cubic yards of demolished buildings, equipment, containers, contaminated soil, and radioactive waste including uranium, radium and thorium.

The disposal cell is covered with rip rap.

Three small towns were located here in the early 1900’s but during the early years of WWII everyone was moved out to make way for a huge TNT production complex. The site later became a center for uranium ore processing. In the early 1960’s plans were developed to produce Agent Orange at the site, but this never came to fruition and the facility was closed in 1969.

1.5 million yards of contaminated fill below me

From 1941-1968 the site generated a variety of toxic chemicals and radioactive waste. Much of this was discarded into unlined ponds, abandoned in barrels and buildings and dumped into a nearby limestone quarry. The quarry is located less than a mile from a well field that supplied drinking water for St. Charles County. Nuclear waste was brought from other places and discarded here as well. Obviously, the area was heavily contaminated and very dangerous. The Department of Energy invested nearly a billion dollars in the clean-up. The interpretive center presents all this information and is definitely worth a visit.

Francis Howell High just to the northeast

I was there to see the prairie though so after hiking up to the top of the disposal cell (and seeing Francis Howell High School a bit less than ½ mile to the northeast) I descended and explored the prairie. I saw little wildlife - a few blackbirds and finches - but there were numerous deer tracks and the occasional raccoon scat.

The prairie is short - about waist to chest high - unlike the Heartland Prairie in Alton where grasses and forbs grow six to eight feet high. The plants are still getting established after a decade of growth.

The disposal cell is impossible to ignore.

I wonder if the slow growth rate has anything to do with the soil at the site. The underlying soil profile has been heavily altered. Although the entire area was prairie during the Nineteenth Century, up to several feet of contaminated soil was scraped away during remediation. Clean soil was brought in and spread across the surface. Soil fertility was amended but perhaps the new soil was not of the highest quality.

Hairy mountain mint

The topographic contours of the site were constructed so water drains away from the disposal cell. Clearly, very little remains of the original in situ environmental variables that contributed to the health of the presettlement prairie. I suppose it is a miracle that plants are growing at all! It would be interesting to talk to Jon Wingo and hear his thoughts and observations about the development of the prairie at this location.

Compass plant

Nonetheless, the Howell Prairie is a beautiful place and I recommend that anyone interested visit it. The plant growth is healthy. Even in the dead of winter there is a lot of green foliage at ground level and the dormant plant stalk are incredibly beautiful – full of intricate shapes, details, swaying and rustling in the wind.

The site is so large that a number of landscapes are present. Tall grass prairie dominates and little bluestem (Schizachyrium scoparium) seems to be the most common grass across the prairie.

Cattails

There are a couple of swampy areas where scrubby trees, cattails and Carex spp. are scattered among the prairie plants. Slopes seem to have a different species composition than hill tops. In several places one forb dominates with other species mixed in. These concentrations include asters, beardtongue (Penstemon digitalis), bee balm (Monarda sp.), rattlesnake master (Eryngium yuccifolium), and stiff goldenrod (Solidage rigida).

Grey coneflower stalks

Other species noted include compass plant (Silphium laciniatum), false indigo (Baptisia sp.), mountain mint (Pycnanthemum sp.), bush clover (Lespedeza capitata) and prairie clover (Dalea purpurea). There are many species of grass as well. I noticed a small stand of Iva annua in a less well drained area behind the disposal cell. I doubt this was sown intentionally. It likely represents a natural recolonization of this species from the Missouri River valley just a couple of miles away as the crow flies. You can access a partial list of species installed at Howell Prairie here.

Monitoring well #2038

If you visit don’t expect wilderness. The sound of traffic on Highway 40 (maybe a mile and a half to the north) was an omnipresent low hum. The Department of Energy continues an intensive groundwater monitoring program in the area. You are never out of sight of several of these clusters of bright yellow posts. As I mentioned earlier, the disposal cell is such an enormous feature that, as long as you are vertical, you never lose sight of it.

More monitoring wells at the tree line

My visit left me with a profound sadness over our seeming propensity to screw up everything we touch. At the same time I realize that our knowledge increases and we try to do better all the time. The people who built this place probably didn’t realize they were destroying the environment. They likely thought that dumping TNT residues into a huge unlined pit full of water was the best way to dispose of it.

One of the most shocking things I saw were pictures of soil cores taken from the disposal pits. Seeing those rainbow-hued soil cores really brings home what was going on here. I think the take home for me is that we should keep an open mind to the potential harmful effects of our actions. ‘Walk softly on the earth’ is a good position to start from. Think about how our purchases, our choices, our daily activities might be helping create some future environmental disaster. We might not prevent it. But we might.

As I was driving home the huge moon rose above O'Fallon. I looked at that gorgeous moon shining down on all that clutter - the stores with their garish lighted signs, Highway 40 full of automobiles belching carbon, and row upon row of hideous cheap suburban housing. I despaired again and felt ashamed that this is what we do - here on such a wonderful planet, under the gaze of this beautiful and mysterious moon.

Mayor's Sustainability Summitt speech

Well, now that the prairie is installed and winter is on us we are in waiting mode until spring when the temperatures rise and the plants emerge. Can't wait to see what comes up and how it looks. The prairie plants we planted should grow quickly and flower in 2014. Some of the seeds we planted will come up and a few of those may bloom as well. Other seeds will sprout over the next 2-5 years. Some of the plants we put in will eventually die or be out-competed by more vigorous species. The prairie is going to be an evolving landscape as new species emerge and others disappear.

The final action we took was to attend the Mayor's Sustainability Summit on November 9th and present our project to the mayor and to the city. The following is the text of my presentation. Once again, thanks so much to everyone who came out and lent a hand. This experience has been fantastic!

Speech at Mayor’s Sustainability Showcase
Good Morning! In the next five minutes I will give you some background on the Thurman Gateway Prairie Restoration Project, tell you why we chose the site, explain what we did and what we learned, and end with a brief view to the future.

Hwy 44 creates a physical barrier between the Shaw and Botanical Heights neighborhoods. Walking or biking between the neighborhoods is difficult and involves jockeying with cars on Grand Avenue, Tower Grove or Spring Avenue. Thurman Avenue is the other connecting street but it has been closed to automobiles for thirty years. This would be an ideal route for pedestrians and bicyclists but, until this summer, the street entrances were a tangled mass of trees, brush, vines and debris. The area looked dangerous and was avoided by many neighbors. The appearance of this area created a social barrier between the neighborhoods.

Last year a group of neighbors began a discussion about beautifying the area. Plans to repave the street, install new lighting and paint a bike lane on the pavement were discussed and approved. The underpass will be transformed into a pedestrian and bike friendly pocket park but no attention was given to the natural habitat potential of the site’s four sloping grassy sections of highway right-of-way.

This is not surprising. We often think of cities as human and domestic places, areas given to industrial activities, lost to nature. We think of countryside as the proper place for nature, wildlife, and wilderness. One result of this viewpoint is that we live with mile after mile of urban highway right-of-way cordoned off, planted with non-native grasses, and mowed intensively as if it were an enormous lawn. Native birds, butterflies and pollinators have no home in this landscape and neither do we!

Those of us who garden know this old viewpoint is nonsense! We know that cities are managed landscapes but nature is here! As cities grow larger and larger, where else will nature survive? We have to make room for wilderness all around us, not just in our nature reserve and parks, but also in our front yards, back yards, empty lots, parking lots, and highway right-of-ways.

So, knowing our neighborhood history, we already knew that Shaw was once a prairie called the Prairie des Noyers. Local conditions favor the prairie ecosystem and this is the kind of native landscape that makes sense in Shaw. We decided to landscape the new pocket park at the Thurman underpass with a beautiful prairie restoration project.

Thanks to 208 neighbors and friends who volunteered at least 624 hours of their time we cleared the site of debris, removed non-native vegetation, planted ¼ acre of prairie and mulched the entire area.

Thanks to funding from the Mayor’s Office and Brightside St. Louis we purchased and planted 1,150 live prairie grasses and flowering perennials. Just to make sure, we also broadcasted nine pounds of prairie and cover crop seeds. Our restoration project returns 78 species of native prairie plants to Shaw. These plants will in turn attract and feed native bees, butterflies and song birds.

We were assisted by the City Streets Department, the City Forestry Department, the Water Department, and the Missouri Department of Transportation. Volunteers came from the Shaw and Botanical Heights neighborhoods, The Word at Shaw, Faith in Action, the Lutheran Elders of the St. Louis district, Epworth Children and Family Services and from St. Louis University.

Along the way we decided to make the project relevant to every participating group. We developed a short introductory presentation that I delivered at every work day. This presentation included the passing of visual aids (pass these around now) demonstrating the flowers, the birds, the bees and butterflies that would be brought back through our volunteers’ hard work. The volunteers told us this approach got them excited to be a part of the project and made the work worthwhile. They could see the future outcome of their work and felt like they were a part of something important!

We also discovered that many neighbors do not understand the importance of prairie. Many have never seen a prairie. Others think prairies are ugly and weedy. In response, we decided to create a new non-profit organization, Sustainable in St. Louis (SiSL), to take the project to the next level: from a landscaping project to an educational project.

Through SiSL we have begun to gather a network of ecology professionals and skilled volunteers from across the Midwest to help us maintain and expand the prairie.

We have partnered with the North American Butterfly Association and the Audubon Society to track the return of pollinators and song birds to the site. We are developing educational opportunities for the neighborhood and the city including signs that identify native species, web pages to present the primary habitat data we collect and additional web pages to make available practical information about how you can create native habitat in your own space. Finally, we are partnering with local schools to develop curriculum and internship opportunities that will bring university, high school and elementary school students into the prairie.

Now! This is not where we started! We began with a landscaping project but we are on the way to something larger and richer. Thank you to the Mayor’s Office and Brightside St. Louis for funding the project. I hope each of you has the opportunity to walk or bike through the Thurman gateway in the years ahead to see it evolve.

This is a collaborative project and it will remain so. I invite each of you to not only visit us but to contact us with your suggestions and ideas for making the project bigger, better and more useful to everyone. Thank you!