Naturalist Henry David Thoreau wrote in his journal: "I have an appointment with spring. She comes to the window to wake me, and I go forth an hour or two earlier than usual."

Each of us has something special that catches our attention and tells us that spring is on its way: The tremulous voice of a red-winged blackbird singing "o-ka-leeee" from a still-frozen cattail marsh; ice leaving a lake; the smell of moist soil; or the the sun's warmth. To others it may be the lengthening of daylight, crocus flowers, kite-flying, or golf.

It's the snowy holds of winter disappearing at the beginning of spring and the exquisite fragrance of rugosa roses as spring draws to a close that makes the season so absorbing.

Since Minnesota is in the temperate climatic zone, spring includes the months of March, April and May. But there is a distinct difference between the usual snowy, blustery landscape of early March and the lush green woodlands and lawns of late May. No doubt that's why the two words "awakening season" are used to explain spring.

Some people like to divide spring into two parts. There is the time between early March and mid-April when the scents of moist earth begin and the change in the nature of the sunlight draws people out of doors. Creatures, too, come into the light. Late spring, or the second part of spring, is the time of hummingbirds' return, apple blossoms, morels and more. There are so many changes that it seems as if each day is a season in itself.

Jim Gilbert taught and worked as a naturalist for 50 years.