Star Magnolia

While you are closely examining this tree, shift your focus to the white bumps on the lower branches. This is evidence of magnolia scales, which are a type of soft-shelled scale insects. Scale insects can be very damaging to plants by using their “needle-like mouths” to siphon sugars from the tree, similarly to aphids. The white bumps you are seeing are the defecation of sugary, sappy substances that will occasionally grow a black sooty mold on top. Star magnolias, saucer magnolias, and hybrids of the two species are the most common targets for the magnolia scales. Let’s hope this tree is strong enough to withstand these sap-sucking, creepy crawlers!

Now, take note of the leaves. Depending on the season that you are visiting, you may see different foliage. During autumn, the leaves will start to turn a yellowish bronze color before dying off completely and falling to the ground during the winter. This means the tree is deciduous since its leaves fall off every winter. You may also notice wooly, fuzzy buds that stay all winter long. The fur coating protects these soon-to-be flowers. If you are visiting during late winter or early spring, you may be lucky enough to catch the three-week period that the tree is displaying fragrant white or light pink flowers – it’s one of the earliest flowering trees each year! Each flower typically has 12-18 petals, but specific cultivars can have up to 30. Make sure to soak in its beauty because the flowers don’t stay for long. The blooms are soon replaced by dark green leaves in the summer. Later in the summer, the plant produces bright pink aggregated fruit capsules that later burst open to reveal orange seeds. Many people plant Star magnolias because of how early this tree blooms; it can act as a sign that spring is coming. However, this also makes them very susceptible to frost damage.

The star magnolia comes from the Magnoliid clade of flowering plants, and the fossil record has given evidence that this group dates back to the Early Cretaceous period. In simple terms, the magnolias have been around for a VERY long time. Since they were some of the earliest flowering plants, many of the pollinators you may be thinking of were not around yet. This plant is not pollinated by bees or butterflies, but rather by beetles and flies. Their flowers and seeds provide more evidence that beetles and flies were influential in steering the evolutionary changes in this group. Beetle’s mouths are made primarily for chewing, not careful pollen collection, so this often results in additional plant parts being consumed in the pollination process. Therefore, magnolia flowers have evolved to have leathery, thick leaves and well-protected seeds. The Magnoliids played a huge role in the development and diversification of flowering plants as well as advanced pollinators.

The star magnolia’s impressive flowers are hermaphroditic, meaning they house both male and female reproductive organs on the same flower. The male organs release pollen, and the female organs contain the egg that waits to be fertilized by pollen. They are also protogynous, meaning the female reproductive organs come to maturity faster than the male. The flowers go through a female phase, then a bisexual phase, and finally a male phase. This species is self-compatible which means it is able to be fertilized by its own pollen and there is no research to show that the plant purposely prevents this. This can be helpful when there are no other star magnolia nearby for a beetle to carry its pollen, however, self-fertilization does nothing to enhance the genetic diversity of the species.

I encourage you to continue your journey learning about the wide variety of tree species Rowan University has to offer. If you have a preference for magnolias, I recommend heading over to the saucer magnolia next which is a hybrid between two other magnolia species. If you’re looking for a change of pace, you might go check out the sassafras tree whose roots were traditionally used to make root beer. Happy learning!

These resources are a product of Dr. Sara Wright’s Plant Diversity course in the Biological and Biomedical Sciences Department. My name is Ally Reagle, and I will earn my Bachelor of Science degree in Biology in 2023. I plan to pursue a career in Wildlife Rehabilitation. You can read more about me and the Star magnolia below.