Purple trillium (Trillium erectum)

As you look down on the three or so kinds of violets, wild oats, trilliums, spring beauties, and assorted others in the woods, it's fun to get beyond just the names. Phenology is a frequent term in this newletter, and refers to when nature does what it does.

Patterns are something we tend to notice. You might know when a particular plant blooms, when a species of warbler can be expected, or when you might hear the first clap of thunder. Nature has its pleasing rhythms. The blush of red maple flowers on a nearby hill doesn't just signal the end of another long, dark winter. In some sense it's an "all clear" signal. All is well with the world; the wheel of life is making one more turn.

Maybe more interesting than when something happens, is why that something happens when it does. Let's go back to the wildflowers. Why, for example, are violets early bloomers? For that matter, why are some woodland species (like partridge berry or wood sorrel) in flower in early July, and why is the fall display dominated by asters and goldenrods? Just the luck of the draw, or are some mechanisms at work here?

All flowering plants have a few important things to do each year: they have to produce flowers, get them pollinated, mature any fruits, and then get their seeds dispersed. That's a lot to do in a short Vermont growing season, so why don't they all bloom first thing?

In 1973, a Canadian scientist floated one possible answer. He sampled the nectar levels of spring flowers and found gobs of it in some willows and dandelions. Why would a hungry bug go anywhere else? Naturally, this question assumes that insect pollinators can understand a good thing and stay with it. We know bees are smart enough to learn where the candy store is, but what about a beetle? OK, back to the flowers.

If you're a plant, you don't want to (1) make any more nectar than you must to get insect visitors (you also have to make new tissue), or (2) waste pollen when some less-than-brilliant bug takes your expensive pollen to another species of plant where it just sits. Talk about useless!

So do you enter the nectar wars and make a lot of sugary nectar--or might you move the time of your flowering to get away from what our Canadian friend called "cornucopian" species?

Boy, did that paper stir things up. Whole communities of plants were analyzed to see if competition for pollinators might explain why flowering was spread out over the entire season. Mostly, "no" turned out to be the answer. Oh well, nature loves her secrets.

But could it be that the early ephemerals want to get it done before the canopy closes? And might most of the fall bloomers get away with being late because they can use the wind to move their tufted seeds around? "Birds? Who needs birds?"

There's a lot more to do.

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