Rattlesnake-master sprouting after a prescribed fire.

Rattlesnake-master sprouting after a prescribed fire.

Webster’s Dictionary defines “transition” as a passage from one state to another, from one stage to another, or from one place to another. A second definition is a development or evolution from one form or shape to another. The transition from winter to spring is a transition from frozen, often snow- covered, ground to thawed ground, often moist from the spring thaw. This change can be attributed to the longer daylight, which results from the earth tilting on its axis toward the sun in the northern hemisphere. The longer hours of the day with the sun higher in the spring sky warms the earth, which gradually leads to a season of growth and rebirth.

Some early signs of spring are the green shoots appearing in the small prairie garden areas near the Arboretum visitor center. Fire can be an important tool used to suppress competing non-native cool season grasses and woody vegetation. The fire also releases nutrients—such as nitrogen, phosphorus, zinc, and other chemicals tied up in past year’s dead plant material—to the soil where they can be taken up by this year’s growing plants. The blackened earth where the fire has burned now absorbs more of the sun’s radiant heat, which helps the native warm season prairie plants grow. This transition of converting past seasons’ dead plant material into this year’s prairie goes on each year in the native plant gardens and restored prairies and savannas where fire is used.

The transition from winter to spring brings a season of hope, renewal, and rebirth. It is a time when people act on their intentions or goals. Gardens are planned and started as the soil warms. People start playing sports and riding bicycles after the long winter of not doing these favored outdoor activities. Spring tends to invigorate people. This change of seasons awakens us to a more active life. This transition from winter to spring often passes quickly. Some people refer to it as flying by. Quick or slow, the inevitable overcast days and rain and mud of March turn into the warm days of April with plants turning green with the growth of new leaves that lead to the profusion of May flowers.

Today in the Arboretum we heard frogs calling. You know spring has started when the frogs have come back to life after spending the winter in a state of suspended animation buried in the mud. These are poikilotherms, or cold-blooded animals, which rely on solar heat to warm them, enabling them to swim and make their spring mating calls.

We heard the frog calls and saw a few spring migrants. The robins are numerous now, so are the red-winged blackbirds. One visitor saw a pair of sandhill cranes flying over Curtis Prairie. On Teal Pond we saw a pair of Canada geese and a pair of mallards. Both of these birds occur in the area in low numbers in flocks during the winter, but now we see them in pairs. This is the season when animals often change their behavior in preparation for raising young. You notice this when you see the adult male turkeys doing their mating displays. We watched a chipmunk dash across a patch of lawn. Recently this familiar little mammal was sleeping the winter away in its underground burrow.

In the woodlands there are fewer signs of spring than in the Longenecker Horticultural Gardens, where the yellow flowers of the forsythia stand out from a distance. Like the willows, with their pussy toes, and the vernal witch hazel, with their witch hat-like yellow flowers, the forsythia blossoms open on bare stems before any green leaves appear. Most plants grow leaves from their overwintered buds, thus allowing them to begin photosynthesis to capture the sun’s energy and hasten their spring growth. But some plants—including willows, magnolias, vernal witch hazel, and forsythia—produce flowers first and leaves later. Since these plants flower before insect pollinators emerge, they are mostly wind pollinated.  The magnolias flower a bit later when insects are present to pollinate them.

Walking in Longenecker Horticultural Garden we noticed the bright red flowers of maples. The tree tops have a reddish hue among the otherwise bare branches. On the ground under the trees are numerous red flowers either past their prime and already fallen off the trees or, perhaps, blown off by the strong March winds.

You never know how fast this season of transitions will unfold. With a few sunny, warmer-than-usual days it can feel like spring is here. Then another low-pressure system with several cooler-than-normal and wet windy days slows down the advance of spring. The cloudy, cool, wet weather not only slows down nature’s transition from winter to spring, it also slows down our transition as it reduces our energy, limits our outdoor activities, and makes us yearn for those warm sunny days. Eventually, as the days grow longer and warmer, spring unfolds and summer is here. For some of us this transition seems to pass too quickly because the season of flowers, bird migration, and new growth on all the trees, bushes, and grasslands is one of our favorite times of year.

—Levi Wood