Friday, April 2, 2010

Coltsfoot

While in Jackson County - former Ohio governor James A. Rhodes' home county - this morning, I passed a radiant patch of Coltsfoot, Tussilago farfara. This plant is a true harbinger of spring; one of the first conspicuous flowers to be found along roadbanks. The generic name Tussilago essentially means "a cough"; this plant has long been reputed to be a cure for hackers.

Quite dandelionlike in appearance, Coltsfoot thrives on gravelly road verges and embankments. It is a native of Eurasia, long ago introduced to North America and now widespread and well-established. Thus, it might be considered a "weed".

What is a weed? Ralph Waldo Emerson said "A plant whose virtues have not yet been discovered". Good one, Ralph. A more critical definition might be: A plant that is not native, but is established.

Weeds might be lumped into three categories. The rarely seen curiosities that barely have gained a foothold; common but innocuous species like Coltsfoot; and the truly noxious invaders that deteriorate our native habitats, such as Purple Loosestrife, Lythrum salicaria, and the bush honeysuckles, genus Lonicera.
Coltsfoot is a non-native that really does little harm, at least in these parts. It tends to stay in highly disturbed weedy habitats, and not push out our native species. Elsewhere, it does cause problems by infesting native haunts, though.

In this tight shot of a Coltsfoot's smiling lemony face, we can see the characteristic structure of the Asteraceae, or Sunflower Family. Evident are the numerous narrow ray flowers, or ligulate flowers - the petals - forming a brushy edge around the fertile disk flowers - the cup in the center.


The fleshy, rubbery stems are flexible, and the cauline (stem) leaves are reduced to little more than scales. The flowers, and later the leaves, arise from perennial creeping rootstocks that spread horizontally. Coltsfoot follow the sun, their flowers tracking its movements across the sky.

The common name originates from these leaves, which somewhat resemble the print of a horse's hoof. These leaves were tiny, and for the most part the plants had not yet thrust their chlorophyll-bearing greenery above ground. Once the flowers fade, the leaves emerge and persist throughout summer, becoming nearly dinner plate-sized. This strategy allows the rhizomes to build up and store energy that allows them to shoot the flowering stalks up early in spring.

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1 comment:

rebecca said...

I'll have to keep an eye out for that one...