Horticulture Highlight: Umbrella Magnolia, Magnolia tripetala

I wakened to the singing of a bird;

I heard the bird of spring.

And, lo!

At his sweet note

The flowers began to grow…

            -Annie Adams Field

There are multitudinous flowers everywhere in Mount Auburn during the month of May. Early on are trillium, forsythia, spiraea, serviceberry, fothergilla, magnolia, then on to crab apple, lilac, wisteria, finally displaying azalea, amsonia, viburnum, false indigo, tulip tree among many others. While there have been many magnolias in bloom from mid-April on, herein we focus on one of the later flowering species.

Umbrella Magnolia, Magnolia tripetala, one of the bigleaf deciduous magnolias, is native from Ohio to Kentucky south to Georgia and west to Arkansas and Louisiana, but it is cold hardy to USDA zone 5 (4). Growing 15-30-feet, with a multiple stem, rounded habit, it usually is the 12-24-inch long and 6-8-inches wide leaves which first garner attention. These semi-tropical sized leaves are arranged in whorl-like clusters at the ends of shoots reminding one of an umbrella, hence the common name.

Happening upon it in bloom, will also bring one for a closer view. The white, upright flowers are 6-10-inches across. Unlike other magnolias the fragrance is unpleasant. As with all magnolias the flowers are composed of tepals (when petals and sepals are indistinguishable). Umbrella Magnolia have 6-9 (12) tepals, each 4-5-inches long, with the outer three tepals reflexed back.

The species name given by Carl Linnaeus (1707-1778) in 1737 probably alludes to these outer three tepals. The genus name commemorates Pierre Magnol (1638-1715), Director of the French Royal Botanic Garden at Montpellier, who was the first to divide plants into “families” such as today’s MAGNOLIACEAE.

…magnolias blossoming

like afterthought: each flower

a surrender, white flags draped

among the branches…

            -Natasha Trethewey

Magnolias are not the first angiosperm plants but are among the oldest groups right after conifers. Evolving around 25 million years before bees, magnolias are beetle pollinated. When successfully pollinated these flowers produce visually attractive follicetums (many seeded chamber), 4-inch-long, red and conical shaped. When mature, multiple splits reveal colorful red, pink or orange seeds each attached by a weblike thread dangling them to attract birds to help with seed dispersal. These seeds have high fat content (about 40%) attracting red-eyed vireo, summer tanager, redstart, woodthrush, bluejay, kingbird, cardinal, woodpeckers, mockingbird, towhee, and turkey along with gray squirrel, mice, other rodents, raccoons and opossums. Soon after seeds drop the whole structure dries to a dull brown color and drops to the ground 

In our springtime every day has its hidden growths in the mind…

            -George Eliot

On a future visit to Mount Auburn look for two of our larger Umbrella Magnolias on Halcyon Avenue (at Viburnum Avenue) and Glen Avenue.