Osage Orange; Bois D'arc (Maclura pomifera)

As the bois d'arc is a dioecious tree, the arboretum catalogue is somewhat incomplete. The specimen we currently possess is male, and while males are certainly necessary to perpetuate the survival of the species, we get no fruit from them. The unique green fruit is the most noteworthy feature of this species, something that we would like to show to the Aboretum's guests.

After last winter's ice storm, the arboretum curator discovered a decrepit, sad-looking bois d'arc on a fenceline in Caddo parish, just north of Shreveport. Surrounded by a grove of invasive bamboo, next to an impromptu trash dump, and near an unfriendly pack of local canines, this tree has been lost to the knowledge of mankind for decades. Its presence on a property line is fairly good evidence that it was intentionally planted there. The arboretum curator only recognized the tree as a bois d'arc due to the presence on the ground of a solitary green fruit. Considering the extensive rot and overall poor state of this tree, that may be the last fruit it ever produces. 

Two to three months of cold winter temperatures are necessary for the germination of bois d'arc seeds. We definitely had such temperatures this year. After being collected, the fruit was tossed onto the ground outside, where it sat for the duration of January, February, and March. By the end of March, the fruit was black-and-brown, soggy, and infested with a variety of nasty critters. The seeds were painstakingly extracted with a knife and a pair of tweezers, yielding approximately 100, with an estimated half that number being left behind. This was a messy job. The seeds were washed and allowed to dry, then placed in a bowl of rainwater to set for about a week. After this, they were planted five to a container in potting mix. A couple weeks later with temperatures rising, young bois d'arcs are beginning to push up through the potting mix! We are pleased to see that the old tree has produced viable seed. Providence willing, these specimens will become part of the arboretum collection.

We have a flat of seedlings. About five seeds are sprouting per day.

Here we can see one larger sprout and another which still has the seed coat attached, still covering the cotyledon.

The bois d'arc is pictured center. Almost every visible leaf is from poison ivy or another vine.

Here we can see a few sprouts coming off the trunk, a feeble last attempt to get ahold of some sunlight. The bamboo is winning.

From this side, we have a better look at the trunk and its branches. The tree was able to grow in this location long enough to develop a thick trunk. Unfortunately, it appears that the bambo has outcompeted it in recent years, but, luckily, we found one of its fruits and have thus far had success in our germination project.

Mayhaw Success!

 

These are the arboretum's four mayhaws. This is definitely the most famous, at least in our region, member of the genus Crataegus.

Right now in the arboretum we are happy to see pristine-looking mayhaw fruits, something that we haven't had for more than 5 years.

Not only do we see red-ripe fruit, we also have green fruits coming in behind them. Look how healthy the leaves look! A new era is dawning.

All efforts to control the arboretum's cedar apple rust were unsuccessful. In 2018, we undertook to spray the mayhaws with a fungicide (you can see photos of that here). We made multiple applications and documented the development of the cedar apple rust galls. As previously explained on this blog, we ultimately made the decision to remove the eastern red cedars (Juniperus virginiana) in favor of the crabapple tree and various haws. This process was carried out over several years, as documented in 2021 and 2023.

What we're observing now with the improved health of the Mayhaws (in both leaf and fruit) is that we made the correct decision, insofar as our goals are now being achieved.

Nevertheless, we're not entirely out of the woods. These three groups of mayhaw fruits, all collected today, show that it may be a year or two before the disease is entirely purged. The majority of fruits we observed today were healthy (see far left duo). Some had a small blemish.  A few have been transformed into monstrous mutants, reminding one of John Carpenter's 'The Thing' (see center green fruit, studded with pink horns). If these tell you they're "just fine" or "all better," don't believe them. Finally, as pictured on the far right, we can see that some fruit simply withered on the tree and failed to grow at all. This was a failure for the cedar apple rust as well, as it requires the developed fruit to spread the infection.

This is unsettling to look upon, but we feel obligated to document it. Yuck.

While carefully examining the trees for new fruit, several dead branches were noticed, so a little pruning was necessary. When working around mayhaws, watch out for spines! These branches will poke you.

Flowering Azalea, the Native Kind (Rhododendron austrinum)

 These Azaleas are on fire!

You won't be able to miss this gorgeous shrub.

A distress call is going out: "Help! Please pollinate me!"

The native bees need to get to work; there are a lot of flowers here.

This shrub has more flowers than leaves. As the flowers are in their height of glory, the leaves are just emerging. See our previous post on this.

Orange, yellow, red, green, pink, and every shade between.

Would William Blake consider this to be 'fearful symmetry'? I'd be scared to try and recreate it from memory.

These flowers are not only beautiful and enchanting, they are staggeringly complicated.

As the bees see it (photographed from an elevated position.)

Enjoy this one before it's gone. Only a few days remain!

Trillium recurvatum

Trillium-time is upon us! This beautiful and uncommon group of plants is perennially interesting and compelling, so let's take a moment to chronicle their brief flowering season. 

As documented previously, the arboretum is home to two species of trillium: Trillium gracile and Trillium recurvatum. In this series of photographs, we are focusing on Trillium recurvatum. The Key to Trillium, provided by the North Carolina Botanical Garden, helps to confirm that the species pictured below is indeed Trillium recurvatum.

In this photo, we see two individual trillium plants. A tall stalk supports a little burgundy flower that has three large mottled green leaves.

Do you see the three wine-colored petals that are standing upwards and meeting? This helps us identify our plant as Trillium recurvatum.

This plant is less than a foot high, approximately 10 inches above the ground.

One petal and two filaments were removed to get a better look at the reproductive parts.

The green sepals curve down, between the mottled green leaves (bracts). These sepals touch the stalk (scape).

There are six filaments. The anther connectives are curved inward.

Filaments are more than ¼ inch in length. The flower does not smell bad; there is a faintly pleasant smell, nothing offensive. Following the Key to Trillium, we can conclude that this is definitely Trillium recurvatum.

Phlox in Bloom (Phlox divaricata)

 

This bed of phlox is a perennial (pardon the pun) favorite among the arboretum's guests. Your curator has noticed more than one group using this delightful splash of delicate blue-purple color as a backdrop for photographs.

These gorgeous wildflowers are sure to improve the mood of anyone who can spare a moment.

The patch of phlox has significantly grown over the past several years. This photo, from 2019, shows how the phlox was neatly contained within a flower bed lined with bricks. Today, the bricks are still there, demarcating the bed, but a reduction in spring-time mowing has allowed for this wildflower to naturally spread.

Sweet Olive Blooming (Osmanthus americanus)

 

The tree with an unfortunate lean is one of the best-smelling in the arboretum. But if you want a sniff, you'll have to act fast!

These delicate white, yellow, and green flowers belong to the sweet olive.

They can be found near the Southwest entrance to Mickle Hall.

If you look closely, you will be able to see how many tiny flowers are littering the ground.

They'll be gone soon at this rate!

The flowers are closely packed, so although many have fallen, quite a few remain in each clump.

If you miss them, don't worry. More species will be blooming and for the sweet olive, there's always next year.

Tree of the Week: Willow Oak (Quercus Phellos)

Previously we described two willow oaks that we obtained from local tree enthusiast Gladden Willis. It's been a few years, so it's a nice time to check on those trees. The previous blog post had pictures of the willow oak planted closer to the Student Union Building. All photos below are from the individual planted toward the Fitness Center.

This tree is coming into its own and growing large enough to assert itself. Recently we've added some friends to its base that will keep it company. Who doesn't like native roses?

Our willow oak has a straight trunk, and in this photo we see that, after so many years, the green, plastic nursery tag is intact, describing the tree's origin.

 

Tiny buds are visible on the branches. Leaves are coming soon.

Trunk bark appears to be splitting at the base. Is this an indication of maturity? No damage or infection is visible.