New Recruits

We have four additions to the arboretum catalogue. All four plants are less than a year old. This past spring, they germinated in a large pot at a homeplace north of Shreveport. The pot was, at the time, meant for a satsuma tree. Oak acorns collected from the Centenary Campus were intentionally planted along with the satsuma, so that might explain the oak seedling that was found in the pot, but the other three seedlings volunteered and were allowed to grow in the pot over the course of the summer. On Wednesday, the four young trees were removed from the satsuma pot and transplanted into the arboretum.

 

A black cherry (Prunus serotina) was planted at the top of a slope, in full sun, at the southwest corner of the arboretum. It measures 2 feet, 1½ inches.

 

At the bottom of the same slope, in a sea of oak leaves, a leafless redbud (Cercis canadensis) was planted. The metal stakes marked with pink tape are absolutely necessary for protecting such an inconspicuous tree. It's the tallest individual planted, measuring 2 feet, 7½ inches.

Taking a closer look at the redbud, we see the characteristic zig-zag stem.

Across the sidewalk, closer to the Fitness Center, a red mulberry (Morus rubra) was planted. There are two red mulberry trees growing in full sun toward the top of the slope, so now we will see how the mulberry fares at the bottom, with more moisture.

 

Our red mulberry is 1 foot tall.

 

Lastly, we have a species of oak tree (Quercus sp.). This little tree, only 6 inches tall, was planted toward the top of the grassy slope on the north side of Cline Hall, not too far from the black cherry. We are hoping that this individual is a southern red oak (Quercus falcata). In the fall of 2022, acorns were collected from a mature southern red oak, growing on the Centenary Campus, near the intersection of Kings Highway and Centenary Boulevard. The acorns were planted in the satsuma pot, and in the spring, this oak sprouted, but its leaves do not resemble the leaves of the southern red oak from which acorns were collected. So, what are we to think?

Now, would you say that this oak leaf resembles a duck foot print? If so, then there is no reason to doubt that this is a southern red oak. The experts at LSU explain that, "...leaves of seedlings and saplings typically lack lateral lobes, and have only a few shallow terminal lobes and blade shape that is broadest near the apex, resembling a duck foot print" (Louisiana Plant Identification and Interactive Virtual Tours). At minimum, we must conclude that leaves from a mature tree and leaves from a seedling differ in appearance, so we should be hopeful. But, for now, we will error on the side of caution and tag this individual as Quercus sp.

Southwest Corner of Mickle Hall

Architectural plans for the renovation of the Centenary College science building, Mickle Hall, include an addition to its west side. The building project necessitates the removal of a significant number of specimens from the arboretum catalogue. A small number of individuals can be transplanted; that work has already begun (see here). Unfortunately, most of the trees will perish in the name of progress, as they are too large and too old to relocate. In this post we will continue to document the appearance of the arboretum before the renovations change its layout. Below, we take a look at one of the groupings of plants.

Here we see the southwest corner of Mickle Hall. In early January 2022, a mature post oak (Quercus stellata), in declining health, was removed from this location. It stood to the right of the entrance. During the course of the proposed renovation, we will see the removal of the grouping of plants to the left of the entrance.

All of these plants will be removed. Within the leaf litter, there are several seedlings that could be collected and potted for future plantings within the arboretum, but all of the larger plants will be cut down and/or torn up with machinery.

In this photograph, we see the arboretum shed on the far left. It will also be removed, as Mickle Hall is expected to expand into this area.

The largest individual in this grouping is a toothache tree (Zanthoxylum clava-herculis). We have discussed this individual on previous blog posts, found here. It is very tall and over 15 years old. With the proposed addition to Mickle, it will die. However, looking on the 'sunny side of life', we must note that two seedlings were identified in the leaf litter yesterday, and two young toothache trees have already been transplanted elsewhere (read here).

This toothache tree has grown tall, but the curves in its trunk do not inspire confidence in its longevity, so perhaps we ought not be too upset about its destruction. Furthermore, this photo is a reminder that we ought to carefully stake young trees to encourage good upward growth.

This imperiled individual certainly can boast of having a unique trunk, with all of its bumps and spines. It will take some time for the young toothache trees to develop such interesting bark.

Here we see the reproductive structure of the toothache tree. You can find pictures of mature fruits on an older blog post, found here. Fruits from this toothache tree have successfully germinated in the soil of the arboretum, and, depending on the construction schedule, the developing fruits pictured here might have time to ripen and then potentially germinate.

A French mulberry (Callicarpa americana) grows directly next to the toothache tree, and a coral bean (Erythrina herbacea) grows on the other side of the French mulberry. Given its size and this species' tendency to resprout, the French mulberry could perhaps be successfully transplanted. However, the arboretum collection would best be served by focusing on nurturing the numerous seedlings that this individual has produced. Back in February, we collected five seedlings from this corner and transplanted them to other locations in the arboretum. More French mulberry seedlings remain in the leaf litter.

This French mulberry leaf is 5 inches long. It is floppy, fuzzy and very fragrant. Crush one and think about what you can detect. Some say that the strong fragrance serves as a natural mosquito repellent! 

Underneath, white hairs are visible on the French mulberry leaf.

 

Our greatest loss from this grouping of plants will be the coral bean (Erythrina herbacea). Over the winter, the root structure of this plant was examined, and it looked like it would take a backhoe to pull it up out of the ground―the trunk was large and bulbous. This plant is more than 10 years old and looks stuck in its place. It's unfortunate to lose this plant because it is a very handsome specimen, and, at this moment, it appears to be the only coral bean currently in the collection. There is one more coral bean, but it has not yet put up new leaves this spring.

 

Coral bean leaves are compound: this is one leaf with three leaflets. This leaf measures 7½ inches long.

 

Underneath, leaflets are a lighter shade of green. How would you describe the shape of the leaflet? Spade-shaped?

 

A black cherry (Prunus serotina) and its accompanying Carolina moonseed (Cocculus carolinus) must also be removed according to proposed plans. The black cherry was planted here in April 2019. You can read about its history on an old blog post found here. Pieces of Carolina moonseed resided in this sunny location prior to that time.

 

Taking a closer look at the black cherry, we see an irregular trunk. The trunk has the characteristic handsome bark, but the trunk is curved and divided. It never developed a straight form, turning into more of a shrub than a tree. So, it won't be sad to depart with this individual, especially since black cherry seedlings are commonly found in the leaf litter of the arboretum.

Caronlina moonseed is weedy in the arboretum. There are plenty of locations with Carolina moonseed, but there are few places where we would want to actually encourage it to grow. So, it might be a little challenging to find a new spot for our sign.

Carolina moonseed leaves are neat! Do you see an elephant's head pictured here? Two big ears and a trunk?

Interestingly, Carolina moonseed leaves resemble coral bean leaflets. On the left, we see a coral bean leaflet. On the right, we see a Carolina moonseed leaf. There are two different shades of green, but both the leaf and the leaflet have the shape of an elephant's head.

Underneath, the coloration is similar as well. Holding them in your hand, you can quickly tell them apart. The coral bean (pictured left) feels very delicate this time of year, as if it would easily tear or crumple. By comparison, the Carolina moonseed leaf (pictured right) is rigid. Also, underneath, the Carolina moonseed leaf has fine white hairs and feels soft to the touch.

 

Within this grouping of plants, five individuals are expected to be removed for construction and renovation on Mickle Hall. This is only one of several groupings that are imperiled by the proposed plans.

 

Tree of the Week: Black Cherry (Prunus serotina)

Let's celebrate! This week, we're adding a black cherry (Prunus serotina) to the catalogue. Fair warning: it's not the ideal time to plant a tree in northwest Louisiana. It's getting too hot and the forecast could turn dry at any time. However, a rule of thumb is only as good as the conditions you're dealing with. Recently we've had several ground-soaking rains, and due to the passing of a toothache tree (Zanthoxylum clava-herculis), we had an opening in the landscape. Since it's in a high-traffic area, it pays to fill the void. We found our black cherry on the bench and it's time to hit the court. But one thing's for sure: this rookie will need a garden hose this summer. Will it make it?

This young black cherry is six years old. On November 4, 2013, it was transplanted from the soil of the arboretum into a container. At that time it was a very small seedling. Today, it's a little less than 2 feet in height.

A few of the lower branches were removed to reveal a crooked trunk, which is perhaps the result of growing in crowded, shady conditions. Over the next several years we will work on correcting this crookedness.

The removed lower branches were studied for the characteristics of the species. Simple, elliptic leaves alternate along the twig.

Underneath, the leaves are pale green. These fresh leaves lack the characteristic orange particles; you can find an example of that feature here.

Black cherry leaves are smooth on top with serrated edges. The largest leaves on this young specimen measure more than 3 inches in length.

This past fall, one of our toothache trees died, leaving open a sunny spot. The location isn't completely free, though. The toothache tree had a close friend: a Carolina moonseed vine. The vine was co-habitating with the toothache tree, partially using the tree as a trellis. After the removal of the toothache tree, several pieces of the vine remain.

In making way for the black cherry, the pine straw mulch was pulled back and much of the moonseed vine was cleared.

A portion of the vine is allowed to cling to its designated pole and sign.

Removing the mound of moonseed vine revealed the toothache tree stump.

A shovel and a handsaw were used to remove the toothache tree stump. When it died, this tree was more than 30 years old. This individual never really thrived and cause of death has not been determined. Sometimes you just never know.

Removing the stump loosened the soil and adequately prepared a spot for the new black cherry. No extra digging was needed.

Because no soil amendments were necessary, planting the tree took no time.

Although not planted at the best time of year, we still expect big things from this little tree. First, we count on its trunk straightening, resulting in a relatively upright, pleasing posture; second, in a few years it ought to provide shade to the two nearby sidewalks; third, if the moonseed remains in its present location, the black cherry will then provide a sturdy trellis for the vine to climb; and finally, we expect fruits!

Tree of the Week: Black Cherry (Prunus serotina)

This week, we must appreciate the robust black cherry (Prunus serotina). This specimen has gone above and beyond what we could ask of any tree; it's been a real self-starter. Without any assistance from the arboretum staff, this black cherry germinated in the perfect spot, next to the long, white wooden bridge. In 2004, its efforts were first noticed, and it was included in the arboretum collection, as a volunteer for the native-plant-cause. Furthermore, after the tree established itself, it began to serve as a trellis for a native wistera vine (Wisteria frutescens). Anyone who has cultivated wisteria vines understands that this is not for the faint of heart, given the aggressive nature of the vine. Finally, despite the sweltering conditions of the season, this very special black cherry provides tasty victuals, in the form of its famous black fruit to arboretum guests, mostly birds.

When standing in the full sun during the heat of the day, everything is a blur.  Our tree of the week is pictured center, but it is almost indistinguishable from its surroundings. 

Stepping into the shade of a maple, we have a better view: the black cherry is pictured center, to the left of the white bridge and to the right of a laurel oak (Quercus hemisphaerica). This is a nice, comparatively comfortable spot, and the black cherry is contributing to the shadiness.

Covered in thick, woody vines, the black cherry leans westward, perhaps vying for extra sunlight, as this is considered a shade-intolerant species.

Native wisteria (Wisteria frutescens) is the only official climber.

Thick, gray wisteria vines are twisting around the black cherry trunk. Several other vine species have volunteered here and are routinely cut back. 

This is maturing black cherry bark: smooth and beautifully ringed immature bark appears to be flaking off, revealing rough, dark blocks of bark.

Black cherry leaves are simple. They are narrow with an elliptic shape that tapers off to a point. They alternate along the branchlet.

The upper surface of the leaf is glossy and green. Leaves are approximately 4 inches in length, but leaf-length can vary by 2 inches.

The lower surface of the leaf is light-green. Little orange particles line the midrib. This picture also shows the serrated edges.

Fruits are hanging from the branches this week. They are going fast. The birds don't allow the fruits to fully ripen; most are plucked and disappear down the bird gullet before they turn black.

New leaves and fruits are pictured on the same twig.

These ripening fruits measure under half an inch. When fully matured and at peak flavor, they will be black.

There are three other black cherries in the arboretum collection. Last year, in late May, we disussed one such speciman. You can read about that individual here. It's an older tree, but its bark looks less mature.

For more information about this species consult the following:
Virginia Tech Dendrology
NC State Extension