You’ve heard of shrinking violets? Well, like many introverts, violets can go ballistic.
Nashville yard violets are violet again, and are “shooting” seeds at the same time.
I’m talking about our Common Blue Violet / Viola sororia, a native wildflower I adore.
In my yard the showy violet flowers take a summer vacation, then resume sporadic bloom in the fall. I’ve seen them in winter, under snow.
But spring is their flowering heyday, and also when the babies sprout. That’s when you can find dozens of tiny seedlings under each mama plant. The babies are easy to move wherever you want free, carefree, edible, semi-evergreen, and native groundcover.
Those spring babies come from seeds that are shooting NOW.
What to Look For:
But the pod isn’t really a pod: it’s a FLOWER: a secret flower.
Yard violets make two sorts of flowers:
1) the open, purple/blue kind with petals, and
2) the closed kind, with no petals.
The dragon jaws are the closed flowers after they burst open.
“Cleistogamous” describes the closed flowers, and it means “closed marriage.” No need for pretty petals or colors to lure insects: these flowers pollinate themselves, in private.
Here’s the ballistic part: when the jaws open, they dry out, bit by bit, and release the teeth (seeds) via “ballistic dispersal.” Mechanical ejection!
But because the flower stems are usually down low, sometimes at the soil line, seeds can fall back around the mama plant, which can explain why so many babies encircle mama in spring.
Trick or Treat
Violets use another bold move in reproduction: bait.
Each seed is equipped with a tiny treat: a blip of fatty goodness to lure ants.
Ants carry the seeds home, feed the fatty blip to the larvae, and then toss the seed in the trash. This dispersal method ensures distance from the mama plant, and can spread violets farther than the low shots that fall nearby. Plus, ant trash tends to be a fertile place for seeds to sprout.
I’ve known this for ages, but never tried to SEE the treat on a violet seed. This time, I took a hand lens to the kitchen table and tried . . . and tried. . . with fresh seeds and older seeds, white and black.
Different violet species have different sizes of treats. (The real term is “eliaiosome”, but let’s say “treat.”) The treats are attached near where the seed was attached. Otherwise, an ant could straddle the open dragon jaw and graze the seeds without taking them anywhere.
My Viola sororia treats must be a sad disappointment to local ants. The only package I see is a wispy wing. That’s it. Everything else is seed-coat.
But in pictures of the English violet (the original “shrinking” violet), the treat is obvious. It’s plump! It’s alluring! If I were an ant, I’d snag it and run.
– Are our homegrown violets guilty of false advertising?
– Do they promise sirloins, but deliver Saltines?
– Are they like that house at Halloween who hands out candy corn instead of Reese Cups??
I’ve read that Viola species can differ greatly in size of treat and in amount of ballistic force. With some, ant dispersal (via big treats) is the primary method. In others, mechanical ejection.
So far, I’ve not seen a single ant interested in my dragon jaws, so I’m guessing our yard violets specialize in ballistics. And as I said above, this could explain why so many seeds end up germinating right beside Mom.
Which would mean that our common violets excel at tricks, not treats.
Look around for a violet near you.
And then check for dragon jaws?
Viola sororia: free, native groundcover; lawn diversifier; butterfly host-plant. Never needs mowing.
Cleistogamous: closed flower that relies on self-pollination.
Chasmogomous: open flower that usually relies on cross-pollination.
Myrmechochory: dispersed by ants.
Elaiosome: the blip of tasty fat on a seed, which entices ants to tote it home for Junior.
Watch violets go ballistic in slo-mo in this Smithsonian video: (the first 30 seconds)
-Here’s a beautiful post at the Natural Web by Mary Anne Borge on some of our most charismatic woodland flowers and their common denominator of elaiosomes: https://the-natural-web.org/2014/05/03/a-carpet-of-spring-beauty-woven-by-ants/
-Awkward Botany has this great page on the chubby elaisomes of the English / Sweet violet, Viola odorata: The Hidden Flowers of Viola.
-Common blue violet as a butterfly host plant? See this page at the Xerces Society. Violets have a specialist mining bee, too!
-More about Viola sororia reproduction, here.
-Study: “Relative importance of ballistic and ant dispersal in two diplochorous Viola species (Violaceae),” here.
-The three-jawed Snaptrapper, from “How to Train Your Dragon.” (#uselessknowledge)
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Joanna Brichetto is a naturalist and writer in Nashville, the hackberry-tree capital of the world.
She writes about everyday marvels amid everyday habitat loss, and her essays have appeared in Creative Nonfiction, Brevity, Fourth Genre, Hippocampus, The Hopper, Flyway, The Common, Stonecrop Review, The Fourth River and other journals.