Magnolias not just a Deep South species
Mention magnolias and images of plantations and mint juleps come to mind. But here in Western North Carolina we have an array of magnolia species that thrive in an upland hardwoods setting. These trees are most noticeable, of course, in spring or early summer when they produce the showy flowers that have made them famous, but they lend a graceful touch to our landscape year round.
In the southern highlands from southwestern Virginia into north Georgia there are seven species belonging to the Magnolia family. The very common tree we call “tulip popular” actually belongs to this family but is classified in a separate genus from the “magnolias” proper. Two evergreen species introduced from more southern climes that might rarely appear around old home sites in the mountains are the “sweet bay” (Magnolia virginiana) and the “southern” or “bull bay” (M. grandiflora).
A species that might rarely appear in WNC is the “big leaf” (M. macrophylla). A 1981 publication issued by the University Botanical Gardens in Asheville reported it to be “rare in the mountains, its range being sparse and spotty in range. A stand along the French Broad River near Asheville is reported.” More recent surveys locate the species in east Tennessee, north Georgia, and the piedmont region of North Carolina, but do not report it from Western North Carolina per se.
So, that leaves us with three native species that we are likely to encounter while tramping around in rich woods and coves: “cucumber tree” (M. acuminata), “umbrella magnolia” (M. tripetala), and “Fraser’s magnolia” (M. fraseri). All have deciduous leaves and bloom in April and May.
They are readily distinguished by leaf shape. Fraser’s has prominent eared lobes at the base of the leaf where it joins the stem. The other two have leaves that join at the stem without lobes. The umbrella species tapers rather sharply to the stem, while the cucumber species leaf is more oval in appearance as it joins the stem.
The cucumber tree is so-named because of the clasping greenish-yellow petals it produces that tend to blend with the leaf and stem colors. It fruits — often in exotic asymmetrical forms — in August and September.
Umbrella magnolia came by its name because of the broadly elliptical 18- to 20-inch leaves clustered near the ends of its branches. It fruits into October and is therefore the woodland species you’re most likely to observe during the fall color season.
Fraser’s magnolia is named for the Scottish plant hunter, John Fraser, who also discovered Fraser fir and purple rhododendron. It is an upland tree that rarely strays out of the highlands region and is therefore also called the “mountain magnolia.” It produces fruit from late July into early September.
Magnolia cones are attractive scarlet to rust-brown aggregates composed of numerous pod or pocket-like follicles, each containing one or two crimson seeds the color of nail polish. When the cones reach the stage whereby seeds are ejected from the fruit pockets, a curious scenario ensues.
Instead of falling immediately to the ground, these seeds remain suspended in the air attached to slender, almost invisible threads. These are called “funicular outgrowths” in botanical manuals. (“Funicular” means anything operated with strands.) Look closely at these with a pocket lens and you’ll find they are rubbery in consistency and vary in length. Indeed, as the seeds come out of the follicles they do so in a spiderman fashion, with the threads elongating according to the weight of each seed.
If you take a cone that is just beginning to exude seeds and place it upright on a sunny windowsill, this process can be speeded up and readily observed. Some will hang on threads up to nearly three inches in length before the link is finally severed. And some seeds remain suspended for many days, if not weeks, before falling.
Why? The most obvious explanation would seem to be that this tree has adapted itself to cater to animal dispersers capable of distributing seeds at a considerable distance from the parent. Birds are the obvious choice. And they can best locate the bright red seeds dangling in the air rather than on the ground.