ENHS Nature Trails November 2001 Article 2

Natural History and You - The President's Forum
by David Wagner

Winter - Season of my Content

As autumn moves into its final weeks, we look forward to what people around here laughingly call winter. Ah, winter! Too often the notion of winter conjures up a season of hibernation and dormancy. My dictionary suggests winter signifies ". . . a period of decline, decay, inertia, dreariness, or adversity." How wrong this is for us here in the Willamette Valley of western Oregon! We have merely entered the rainy season, the long, wet season that connects fall with spring. Only in the occasional years when snow falls can we claim a moment of winter here in the valley.

The onset of the rainy season brings on a new life to the woodlands and fields. It is true that the deciduous trees like oaks and maples, and most of the woody shrubs, drop their leaves and enter dormancy, but most of the native plants spring to life in the "winter" and actually have their primary dormant period in the drought of the summer. The mosses and lichens are entering their main season of growth and reproduction. The perennial herbs are stirring at this very moment, charging their leaf primordia to burst above ground with burgeoning foliage. They appear prominently around Christmas. Watch for the tall larkspur, cow parsnip, and poison hemlock to be the first really big leaves to come up. cont.

Then, there are the winter annuals. I love to watch them grow. These are plants that germinate with the coming of the fall rains and grow all winter. They are among the first to bloom in the new year, long before most people can think of spring. Most will set seed before you get your garden well started. The most prominent weeds in town (winter annuals) are aliens with one exception. The native western bittercress is as successful a weed as any alien in your garden. It is the farthest along, too. Look at the little silhouettes accompanying this piece. The bittercress already has a half-dozen leaves while most have only one or two.

I made this series of silhouettes to help folks identify the common seedlings they see when out for a walk. Seedling i.d. is a little trickier than flower identification, a winter challenge. Note almost all these have two cotyledons, the seed leaves that give the name dicotyledon to a major group of flowering plants. It's interesting that for most of these the cotyledons are very different from the typical leaves of the plants. Only the chickweed has cotyledons much like the typical ones. And maybe the bittercress--the only cotyledon left on the seedling is already withered. My favorite is the bedstraw. It has two huge cotyledons that are bigger than any of the leaflets of the plant until it gets around to putting on summer leaves.

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