Late Spring Flowers

Our long, rainy, pleasant spring officially concludes next week with the Summer solstice. In the photos below, we have two late-Spring flowers to compare. Some flowers are showy, with flashing color that catches the eye; others are small and nearly hidden. 

These bright yellow flowers are certainly of the former eye-catching variety. Golden St. Johns wort (Hypericum frondosum) has been part of the arboretum collection since 1990. It was initially planted near Mickle Hall. After about 20 years, surrounding trees and shrubs grew up around it, blocking too much of the sunlight, steadily reducing the size of the shrub. So a few years ago we took action to preserve the small remaining shrub. It's been transplanted to a more open area, along the gravel path that runs between the Fitness Center and the Student Union Building. 

  

Bees were so active on the St. John's wort that they were difficult to photograph! Slow down, ladies, you're too busy!

 

French mulberry (Callicarpa americana) also flowers in late spring. Clusters of tiny white flowers can be found on the numerous French mulberry shrubs spread out across the arboretum. 

These seemingly non-descript flowers introduce a contradiction when compared to their later product:  clusters of beautiful purple berries that brighten the sweltering August landscape.

April Flowers

 Here at the end of April, we have a beautiful assortment of native wildflowers to share.

 

The oak-leaf hydrangea (Hydrangea quercifolia) shrub is full of large flower clusters.

Oak-leaf Hydrangea (Hydrangea quercifolia) panicle

Swamp Rose (Rosa palustris)

Two catalpa (Catalpa bignonioides) trees grow near the Fitness Center. Be sure to look up to find the large flower clusters. Individual flowers are scattered in the grass, too.

Around the trunk of this dead eastern red cedar, you can find foxglove, strawberry bush and maypop flowers.

Foxglove Beard-tongue (Penstemon digitalis)

  

Strawberry Bush (Euonymus americanus)

Ants were busy working the pollen of the strawberry bush.

Maypop (Passiflora incarnata)

There isn't just one flower on the mapop vine. Note the flower buds on the verge of opening.

Beetles were congregating on the maypop flowers.

 

Spiderwort (Tradescantia sp.)

 

Spiderwort (Tradescantia sp.)

  

 

Prickly Pear (Opuntia humifusa)

 

Coral Bean (Erythrina herbacea)

Lizard tail (Saururus cernuus) and flowering magnolias (Magnolia grandiflora) are also flowering right now, and they will continue on into the month of May.

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.

Red Buckeye (Aesculus pavia)

On October 25, 2023, first-year students collected and planted seeds from red buckeyes in the arboretum. Approximately a month later, seedlings emerged from the dirt. Now, 16 months later, we see the first flowers! That's fast development.

Professor Rachel Johnson brought two groups of students to the arboretum for tours. The first group was from an 8 a.m. class. Students picked up 5 seeds and planted them in this spot, marked by the metal tag.

At minimum, three of the five seeds germinated. One plant remains, and it is short and wide, and it has one red panicle. 

This is full sun. Online literature says that red buckeyes can grow in full sun or shade, so this is one of our experimental spots for full sun conditions. The majority of our other buckeyes grow in part or full shade.

Students from Professor Johnson's noon class also planted 5 seeds. They were slower to germinate by just a week or two. Several seedlings emerged, and died back, and started again.

Today, we see two little plants. One is significantly larger than the other and it has one red panicle.

The arboretum has a steadily growing collection of red buckeyes. We are really hoping to draw in the ruby-throated hummingbirds with these clusters of pretty red flowers.

You can read more about the germination project on an earlier post, found here.

 

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.