Architect César Pelli, who designed some of the world’s tallest buildings, observed: “The desire to reach for the sky runs very deep in the human psyche.” We humans are not alone is this yearning. Plants may be even more determined to go skyward. We all know that all manners of plants, from sunflower to California Redwoods, aspire up. It is, in fact, survival that leads them all aloft, and their construction that enables their ascendance.

Plants are the epitome of perfection in this realm of reaching, and a core part of their success is their stem.

We all need structure in our lives and a plant’s stem provides that, and more. As spring approaches and plant growth accelerates, plant stems are front and center in their vertical aspirations.

Stems are simply an organ of a plant, which can be fleshy fibers or hardened wood (trunks are stems), vital for plants to grow, compete and thrive. The functions they provide are astounding. They provide support for leaves, flowers, twigs, fruits and other plant parts; transport water, nutrients and carbohydrates between the leaves and roots of the plant; provide defense from infection and predators; help achieve photosynthesis, and give plants the physical height needed to out compete their rivals and soak in sunlight.

While all these functions may seem obvious to us, and perhaps even reminiscent of a grade-school lesson, the perfection of form and function is worth another look and perhaps could even inspire a home-school lesson.

Three layers — the epidermis, ground meristem and vascular tissues — compose the anatomy of a plant’s stem. Considered the skin of the stem, the epidermis can be covered with a waxy cutin or cork-like coating (creating bark) which protects the interior stem layers. On the epidermis, nodes (which are the places where new leaves and branches grow from) and internodes (the featureless areas between the nodes) can be observed.

Inside of the epidermis are the vascular tissues that fulfill the roles of food and nutrient transport. Two types, xylem and phloem, function by moving materials within the plant. The xylem transports water from the roots to the leaves and the phloem moves carbohydrates, ions, protein and hormones between the different parts of the plants. Maple syrup surprisingly comes from the xylem and during its harvest is the only time when that fluid is rich in sucrose. The last and center layer, or cortex of the stem, is the pith.

The growth of stems provides instruction in math also. Consider that the leaf arrangement on some stems and patterns of the branches spiraling around the trunk sometimes employ the Fibonacci sequence, or golden ratio, to describe their growth and position. The Fibonacci sequence is a series of numbers whose members are the sum of the two preceding numbers. Picture the bottom of a pinecone or twist of a snail shell to visualize the Fibonacci phenomenon. In addition to stems, seeds, petals, leaf veins and other parts of the plant may also use the sequence.

We also use stems for food. Consider asparagus, celery, and rhubarb as favorite edible stems.

As our victory gardens grow and nature’s spring botanical expansion continues, remember that so much of these plants’ successes and survival stems from the mightiest cells of its simple stalk.  

Suzan Bellincampi is director of the Felix Neck Wildlife Sanctuary in Edgartown, and author of Martha’s Vineyard: A Field Guide to Island Nature and The Nature of Martha’s Vineyard.