Mention the word “thistle,” and for a lot of us, the first thought is probably weed.

Something prickly growing where it isn’t wanted. Something to mow down, dig up, or spray before it spreads.

But not every thistle is an invader.

This one is the wavyleaf thistle, Cirsium undulatum, a native North American plant—and when you get close enough to really look at the flower, it becomes considerably harder to dismiss it as just another weed.

I took the photograph at the Aldo Leopold Vista Picnic Area along U.S. 180 in western New Mexico on October 10, 2011. I recently ran across the image again and put it through PictureThis, which identified it as wavyleaf thistle.

The identification certainly fits what we’re seeing.

What appears at first glance to be one enormous purple flower is actually a flower head made up of many individual tubular flowers called florets. They crowd together into that wonderful explosion of pink, magenta and purple. Some of the long florets are tipped with pale pollen, giving the flower an almost frosted appearance.

Then there is the business end of the plant.

Below all that color is a formidable collection of spines.

Thistles aren’t subtle about discouraging animals from eating them.

A Native, Not an Invader

That’s an important distinction.

Several thistles found in the United States were introduced from Europe and Asia and can become serious agricultural or ecological pests. As a result, “thistle” has acquired a pretty bad reputation.

Wavyleaf thistle is different.

It is native to North America and occurs across a broad portion of the continent, particularly in the Great Plains and West. It grows in open country—prairies, grasslands, roadsides, dry slopes, and other sunny places.

Its common name comes from its leaves, which have noticeably wavy margins. The foliage often looks grayish or silvery because of the fine hairs covering it.

The plant is well adapted to exactly the sort of dry landscape visible behind the flower in this photograph.

And unlike an introduced invasive plant occupying a landscape where it doesn’t belong, native thistles are part of the ecological community that developed around them.

A Little Restaurant With Spines

To us, that flower is attractive.

To an insect, it’s a restaurant.

Native thistles provide nectar and pollen for bees, butterflies, and other pollinating insects. Later, when the flowers mature and produce seed, birds can use them as a food source.

That makes the plant a good example of something we sometimes forget when deciding which plants are “good” and which are “weeds.”

Nature doesn’t organize plants according to whether they’re convenient for people.

A plant can be prickly, inconvenient, and decidedly unpleasant to step on while still having an important place in its environment.

Getting Close Changes Things

That’s one reason I like photographs like this.

From twenty feet away, it’s a thistle.

From two feet away, it’s a purple flower.

Get close enough to photograph it like this, though, and suddenly there’s an extraordinary amount of structure packed into a few inches.

Hundreds of lines radiate outward from the center. Colors shift from deep magenta near the base to pale lavender at the tips. Pollen clings to individual florets. Beneath it all is that armored green flower head.

The second thistle in the background strengthens the photograph. It’s far enough out of focus that it doesn’t compete with the main subject, but it shows the flower in front isn’t standing alone. We’re looking at a plant living in its landscape.

I took this photograph fifteen years ago.

At the time, it was probably simply an interesting flower worth pointing a camera at.

Now I know its name.

Wavyleaf thistle.

And perhaps the more interesting thing I learned is that sometimes a thistle isn’t a weed that needs to be gotten rid of.

Sometimes it’s exactly where it belongs.

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