Loblolly Pine (Pinus taeda)

A young pine tree in the arboretum is now in need of a sign. Due to uncertainty about its species, we have delayed creating an official arboretum placard. To see the post from March 2023, when this specimen entered the arboretum collection, click here. 

Upon collection from the wild in a wooded area north of Shreveport, the tree was so young and small that it lacked obvious species-defining features. It just looked like "native pine." Rather than risking misidentification, which can be a more-or-less permanent issue, we left its classification an open question and waited...for years.

In spring 2026, our young "native pine" is looking more grown-up! 

This fine specimen grows on the grassy slope north of Cline Hall, an area that is open and sunny, but is steadily planted with young trees.

We can confidently identify this specimen using photos of its needles and flowers, its male cones. It's a loblolly (Pinus taeda). No surprises here! In our region, this is a default and commonplace pine, especially dominant in forestry. Its lumber is often sold as SYP (Southern Yellow Pine) and its binomial name Pinus taeda is a Latin-Greek mashup that could be translated as 'Pine-pine' or 'Resinous Resin-tree.' This name doubles-down, to an unusual degree, on the piney-ness of this tree.

This tree is developing a proper and upright growth pattern due to its generous allotment of sunlight and favorable position. Young trees in the wild will be spindly due to the "battle of the understory" that most of them undergo.

Here's the source of that delightful yellow dust covering your car, your outdoor furniture, your pets, etc. Achoooooo!

The identifying features that the juvenile tree lacked: fully-developed needles and reproductive structures. This is the first year that we have seen flowers on the tree, and not many are present. 

 

The fully-developed needle clusters come in trios and are around 6-7 inches long. A shortleaf pine would have needles half that length and usually come in twos. Longleaf pine needles come in threes, but would generally start at 8" in length.

 

The pollen cones are yellow, banana-shaped and approximately an inch in length. Longleaf pollen cones are a startling blue-purple or an orange-red. Shortleaf cones are similar in color and shape to loblolly, but tend to be only half-an-inch or a little larger.

 

There are several on-site native mature loblolly pines in the arboretum and on the campus as a whole, so we might argue that the arboretum doesn't need 'just one more loblolly....' However, the campus loses at least one mature loblolly each year, so it's important to continually replace those old pines. And, it's super neat to see the different stages of a tree's development because as they age, loblolly pines lose those lower branches and we only see that beautiful brown, seemingly perfectly round trunk. So, we are happy to have this young loblolly on that grassy slope in front of Cline.

 

For further online reading, please consult the following websites: 

NC State Extension page on Loblolly Pine 

Article on Loblolly from "The Tree and Its Environment" (1990) 

Ladybird Johnson Wildflower Center page on Loblolly 

Sweetgum (Liquidambar styraciflua)

Currently we have only one sweetgum (Liquidambar styraciflua) in the arboretum collection, and it is still very young. The sole specimen originated from a trip to East Texas in 2022. That fall, we collected a pocketful of gumballs from a wooded area in Cherokee County, Texas, close to the small town of Maydelle. Those gumballs were brought back to Shreveport and shaken into a pot of dirt where the seeds overwintered. Three seedlings came up the following spring. On March 10, 2025, we planted one of the three on campus, outside of the arboretum proper: it's on the Fitness Center lawn, between the Fitness Center ramp and the Cline Hall parking lot. Today, we have a hearty young specimen that nicely displays the characteristics of the species. The following photos show the tree after three years of growth. 

An old sign for a new tree. We like to recycle and re-use our materials in the arboretum.

 

The 3-year-old tree is 21 inches tall with a straight and sturdy trunk.

This one is planted *near* the parking lot but not next to the parking lot. Looking into the future, we see a towering tree with an excessive number of fruits that are falling on the *grass* rather than the cars and pavement. Nobody likes a "trash tree"....

 

While this tree isn't quickly growing tall, it is forming a thick trunk. Have the interesting bark formations drawn your attention?

Young sweetgum stems have irregular 'wings' or corky ridges, like our winged elm (Ulmus alata). The contrast between the green branches and the grey plates is distinctive.

This little tree is ready for spring. 

 

Fresh green leaves unfurl in a bold salute to Spring.

 

We see the characteristic sweetgum leaves in miniature.

Now that it's well-established, will it show rapid and vigorous growth this year?

March Blooms in the Arboretum

Spring doesn't officially begin until the vernal equinox, which is still about two weeks away. But the weather, the animals, and the plants have decided that, for us in Shreveport, the season has arrived in advance of its astronomical formalities. 

Glorious flowering from our Mexican plums (Prunus mexicana) this week.

 

At this time, the flowers have a powerful, distinct, and not altogether pleasant aroma.  Nature's a funny thing.

Here we have a post from March 2019 featuring the same delightful Mexican plum blossoms. And a post from this time last year showing our efforts to transplant some new Mexican plums. Leafing-out season will tell us if that was successful.

Elsewhere in the arboretum, you can find flowers of the paw paw (Asimina triloba). These are less-showy. You will need to go looking for these along the drainage channel that runs north to south through the arboretum.

The juxtaposition of these deep crimson-purple bells alongside the green bells is unforgettable.

We attempted some cross-pollination. Good luck, little tree.

See our post from last summer on planting new paw paw and a similar springtime post from 2022 that features paw paw flowers.

Germination Project: Pyramid Magnolia

The Centenary College Arboretum is participating in a pyramid magnolia germination project organized by an international team, the Global Conservation Consortium for Magnolia, headed by the Atlanta Botanical Garden. Your arboretum curator has taken on custody of 15 seeds collected from pyramid magnolias (Magnolia pyramidata) growing in east Texas. The seeds were initially collected in August by a group working out of the Lady Bird Johnson Wildflower Center. In September, we at the Centenary College arboretum agreed to join the germination effort. Our 15 seeds arrived at the campus post office on February 17th, and we potted them the following day. The Seed Propagation Protocol forwarded by the Consortium tells us that seeds from a 2025 germination project had a high germination rate and sprouted, on average, 53 days after sown. Consequently we can expect seedlings to pop up around April 12th. 

We received a total of 15 seeds, separated into three different bags. Each bag was marked with a number.  

 

In one bag, we received 6 seeds, pictured in the above photo, with an identifying number: SB-20250563. We also received two additional bags, one with 4 seeds and another with 5 seeds. 

Each seed has its own 3-inch pot to call home.

 

Seeds measure ¼ inch in length.

 

Our 15 pots are organized in three groups. We are hoping for 15 seedlings!

You can find more information about the project organizers by following these links:

The Global Conservation Consortium for Magnolia 

Atlanta Botanical Garden 

Bois D'arc (Maclura pomifera)

Three bois d'arc trees were planted on campus today. All are about a year old, and the tallest is approximately a foot high. You can read about the earlier stage of this project here, where we describe the collection and germination process.

We have three pots of bois d'arc (Maclura pomifera). Each pot has one main sapling, and there are several smaller saplings in each pot that will need to be trimmed back routinely until their roots die. We had such a high germination rate that we are now having to cut back seedlings that we do not have space for.

Our tallest sapling measures a foot high.

We already see new leaves on these young trees. You can also see a couple of thorns along the stem. 

We planted all three trees on the slope between the Student Union Building and Rotary Hall. They were sited along the southern side of the drainage channel. There is typically a small amount of water in this channel, year-round, so we are confident that the bois d'arc trees will find this to be one of the likeliest locations in the arboretum for their future success. Naturally, they will require frequent supplemental watering during their first summer, as they are not yet established.

A cottonwood (Populus deltoides) has thrived nearby. These trees ought to be great friends and get along splendidly, but there is surprisingly very little reference on the internet to them growing together. This must be due to the restricted natural range of the bois d'arc, which historically prevented it from colonizing all those areas suited to it. Self-described "desert rat" Gary Nored mentions on his blog that creekbeds in west Texas, along the US-Mexico border, are habitats for cottonwood and bois d'arc. Locally, we see mature bois d'arc and cottonwood growing together along the Clyde Fant Parkway. So, our bois d'arc saplings ought to do just fine.

In this photo, we are looking down the same slope, into the arboretum. A cottonwood is pictured at the far right edge of the frame. Our saplings are already planted, but they do not stand out in the landscape because of their small size. However, they are carefully marked with protective posts, and they will most likely grow quickly, making themselves more conspicuous.

 

Shortleaf Pine (Pinus echinata)

 

There is one shortleaf pine (Pinus echinata) in the arboretum collection. It is approximately 30 years old. In October 1997, two trees were purchased from Coyote Creek Nursery in southeast Louisiana. The following month, they were planted near the Student Union Building. Today, one tree remains.

The shortleaf pine is pictured center. It grows next to the sidewalk that runs between the Student Union Building and Cline Hall Dormitory.

The thin, flat plates on the trunk have a reddish tint.

And here we see the work of the yellow-bellied sap sucker (Sphyrapicus varius). There is a fairly straight, diagonal line of holes drilled across the trunk. At least the holes aren't actively weeping.

All of the limbs on the west side of the trunk have detached and falled off, presumably because they were heavily shaded by the nearby water oak (Quercus  nigra). The remaining lower limbs hang toward the open sidewalk, in full sun. 

Luckily this tree still has lower branches so that we can examine fresh spring-time twigs. Here we see reproductive activity. Shortleaf pines are monoecious, which means they have both male and female parts on the same tree. In this photo, we see a cluster of the pollen-producing catkins, and they are not open yet.

This twig was snipped without the aid of a ladder.

Shortleaf can be identified by the "short" needles that typically come in duos.

These needles measure less than 3 inches. By comparison, our loblolly (Pinus taeda) needles measure 7 inches long, and loblolly pines have three needles per bundle. 

Needles were removed so we could examine the catkins. According to Dr. Becky Barlow at Auburn University, catkins form in the spring while cones develop a few months later, higher in the tree. Catkins are a yearly product, while cones take two years to develop. A healthy, mature tree will therefore have staggered cohorts of pollen and cones.

At the current time, the catkins measure less than half an inch long. They will grow larger before releasing pollen.

USDA NRCS page on Shortleaf Pine

USDA Forest Service Southern Research documentation 

NC State University Gardener Page on Shortleaf Pine

The Shortleaf Pine Initiative

Turk's Cap (Malvaviscus arboreus)

Today we're adding a new perennial wildflower, Turk's cap (Malvaviscus arboreus), to the arboretum collection.

 

We ordered two small pots of Turk's cap from Almost Eden. It's a nursery in Merryville, located in southwest Louisiana on the border with Texas. This company has been in business for decades and grows many native plants that are suitable for our climate. 

Our plants arrived in perfect condition, in a long cardboard box, securely wrapped and taped. This box was built to accomodate up to four plants. We only needed two.

One leaf fell off during transit.

The other leaves help us confirm that this is Turk's cap. Although, when ordering plants, you shouldn't always expect to see leaves. Some plants will arrive as bare sticks, and that's okay, too.

But, it's nice to see the dentate leaves!

The nursery has provided a legible and informative tag. How helpful! Note: 'Big Momma' is spelled 'Momma', not 'Mama'. Dr. Greg Grant, a horticulturist in Smith county Texas, brought us this and other cultivars of Turk's Cap.

With the purchase of these two plants, we are hoping to add something extra pretty to the arboretum collection, so it sure would be nice if our two plants live up to their potential: "The deep scarlet red, 1-1/2" long, Turk's turban-like flowers are held upright and are produced in abundance from late spring or early summer until the first hard frost or freeze...."

Our two plants arrived taller than expected. The tallest measures two feet, and the other is 1 foot and 10 inches.

The 3.5" pots were packed with healthy roots that were ready for the earth.

The two plants were planted together near the southwest corner of Mickle Hall, behind one of our black, metal arboretum signs, and under a winged elm (Ulmus alata). The new plantings are inconspicuous in the winter landscape. Hopefully we will have bright red flowers and butterflies to appreciate while trudging up the hill this summer.

Native American Seed Co. classifies this as a good species for hummingbirds.

Dr. Greg Grant, the breeder who created Big Momma, blogs about his love for Turk's cap.

Almost Eden's page for this plant.

The USDA plant page for wax mallow. 

Lady Bird Johnson Wildflower Center page for Malvaviscus arboreus.

Slope Maintenance and Bridge Replacement

 

Another exhausting session of work on the disturbed slope, with temperatures in the 35 to 45 degree range. The clay is thankfully drying out, which makes it easier to manipulate.

Things are looking better, but it will probably be a year or two before nature heals. Since the ground has been so thoroughly disturbed, we ought to have a multitude of volunteers germinate in this spot. It will be interesting to see what comes up.

Going further down the slope, we see that the new bridge is complete! Wahoo! In the arboretum catalogue, this is referred to as 'the long white wooden bridge that runs from Mickle to the Student Union Building'. It's not white anymore.

 

Ought we paint the bridge white? Another color? Or is the bare look of treated lumber pleasing?

The large pile of materials is gone; craftsmen have used it up.

Here we can see the under-structure of the new bridge, along with some new pylons made of concrete block and treated lumber.

The new bridge also makes use of the old pylons.