Wednesday, October 28, 2015

Wednesday's Wildflower: White Heath Aster

Autumn is the season of asters.

They appear when the dry heat of summer sets in, and many of them continue to dazzle us as winter's chill slowly seeps into the landscape.

While I have chosen a single member of this enormous group as my feature for today, I will introduce many others throughout this final post in the series, since they are all lovely to behold, and provide the last lifeline for pollinators before the winter sleep.

White Heath Aster can be found blooming east of the Rockies, its range extending all of the way from Canada to Texas.

It grows in a wide variety of habitats: disturbed areas, upland prairies, roadsides, weedy meadows, rocky cliffs, wooded bluffs, pastures, abandoned fields and vacant lots.

Even though it is very much native, it has a determined growth habit - often holding its own with the most invasive of exotics.

It begins blooming sometime in September, and often lasts right up until November.

The plants grow from 2-5 feet tall, and have a bit of an arching growth habit. Sometimes they lay over and weave through other plants.

The upper stems branch extensively, with oblanceolate basal leaves that become alternate and elliptic in shape as they grow up the stem.

Their delicate sprays of daisy-like flowers are unmistakable.

The blooms have 15-20 white rays surrounding a yellow disc that sometimes appears reddish, especially as the flowers begin to fade.

It also goes by the name Frost Aster, in reference to its late blooming time.

While the plant family, Asteraceae contains everything from sunflowers to thistles to goldenrod, the true asters number around 250 worldwide, with 60 of them native to the United States. There are 36 species that call Tennessee home, and they are all beautiful.

Before we delve into the dazzling world of our native asters, let's clear up a little confusion.

The genus for asters was originally Aster, a Greek  word meaning literally, "a star."

However, apparently botanists thought that was too easy to remember, so the new genus for asters is Symphyotrichum.

Well, that's merely my opinion. The real reason the North American genus was changed was to set it apart from Eurasian species, which also go by the genus Aster. Besides differences in range, botanists identified structural  and genetic distinctions between the asters of different continents. Thus, the new genus was born.

Even though Symphyotrichum [looks it up for the 500th time - I swear, I simply cannot remember this one] is now the "official" genus name, it is anything but new. The name was first proposed in 1832.

The derivation of this tongue-twisting word is Greek. Symphy(o) means to "come together," and trich(o) means "hair."

Not all field guides subscribe to this new genus, however. Some only make mention of it in the notes, but most newer sources use Symphyotrichum.

As if that wasn't confusing enough, other North American asters have been further divided into genera with names like Eurybia and Oclemena, but we won't get into that.

For this blog post I am keeping it simple, and they shall all be simply, asters.

So with that out of the way, let's meet some other native asters.

The most similar species to the White Heath Aster is the Calico Aster (A. lateriflorus).

It is typically found in moist, wooded areas, has coarsely toothed leaves, and discs that are usually purple. They also have fewer rays per bloom, numbering from 8-12.

My Wildflowers
One of the earlier bloomers in this genus is the New England Aster (A. novae-angliae).

It is stout and hairy, growing up to 6 feet tall.

It has alternate, sessile leaves with clasping bases.

The flowers are large and showy, ranging in color from violet to rose to magenta.

They typically bloom in mid-late summer, but will often last much later in the season, especially if you dead-head them.

They can be found across most of the US, preferring moist meadows and thickets.

This is also one of the only aster species mentioned for its medicinal value.

The Cherokee brewed a tea to treat fevers, used the pounded plant as a poultice to ease pain and drank a root tea to treat diarrhea.

New England Asters make an especially nice landscaping addition, attracting a wide range of pollinators.

White Wood Aster (A. divaricatus var. divaricatus) can be found in the eastern US, preferring dry, upland woods.

White Wood Asters blooming along the Appalachian trail at Carver's Gap.
It blooms between July and October.

Heartleaf Aster (A. cordifolius) has a smooth stem and toothed, heart-shaped leaves.

Heartleaf Asters blooming at Cummins Falls
The yellow centers turn reddish as they age, and this late bloomer can be seen growing in loamy, rocky soil throughout the eastern United States.

Aromatic Aster (A. oblongifolius) is an especially showy species that likes dry, open sites.

It is pretty similar to New England Aster, but contains only 15-40 rays, whereas the former has at least 50.

Aromatic Asters blooming on the lakeside bluffs
In our neck of the woods, it is Short's Aster (A. shorti) that is the last man standing, so to speak.

As the leaves fall and frost envelops the countryside, these purple flowers can still be seen spilling over the bluffs and blanketing the roadsides.

Once their flowers fade, I know for certain that the growing season has come to a close.

Very soon, all of the plants we have come to know and love over the season will bow their heads in submission to the coming winter. Frost and snow will sparkle on their skeletons, and creatures of all shapes and sizes will take shelter below them or even inside them to wait out the winter.

It's easy to feel sadness when winter arrives and most of the color is sapped from the landscape. It's easy to feel that it is an end to something beautiful.

But if there's one thing I've learned in all my years of exploring the great outdoors, it's that nature is never static.

Its path isn't a linear one, but circular. Life is in continuous motion, constantly renewing itself over and over.

Below the soil, the dormant plants are still very much alive, and are waiting for the longer days and warming temperatures to tell them to rise in glory once again.

Life can be found everywhere, even in the dead of winter: tracks in the snow, birds flitting through the leaf litter, or coyotes howling in the distance.

Even so, it is with great eagerness that we will greet the coming of spring in a few, short months (or long ones, depending on how far North you may be). The first flowers will push their way towards the sunshine, offering the first nectar for thankful pollinators, and filling our hearts with joy.

I have so loved writing this series. There is always something new to learn, and it's given me a great opportunity to expand my knowledge and rekindle the child-like wonder of the natural world.

... and expanding the little man's horizons, too
My hope is that you, too have enjoyed taking this journey with me. I hope I have inspired you to take a closer look in your own backyard, getting to know the wild plants that share your space. I hope I have given you the tools and confidence to identify the plants around you, and ignited a spark that will expand into a lifetime of learning.

I'm sure I'll find more to write about during the next few months, but I do plan to start this series again next March, since there are still so many more wildflowers to cover!

Thank you for joining me for Wednesday's Wildflower! See you in the spring!

Click here to read about last week's wildflower, White Frostweed


Wildflowers of Tennessee, the Ohio Valley and the Southern Appalachians - Dennis Horn & Tavia Cathcart

Wildflowers of Tennessee - Jack B. Carman

Cherokee Plants and Their Uses - a 400 Year History - Paul B. Hamel and Mary U. Chiltoskey


  1. What a happy little flower! Thanks for sharing on My Flagstaff Home!


  2. Thank you for this post. My grandmother adored asters and always had several plantings. I'm thinking I need to bring some back into my garden.