The Creepiest Native Plant I Know

By Kathy Purdy October 24, 2018 – Posted in: Native/Invasive

It’s a scene straight out of a horror movie: a thread-like orange stem emerges from the ground, circling around counter-clockwise, searching by smell* for a potential victim. When it finds an unsuspecting, vulnerable plant, it wraps around it and pierces the victim’s stem, sucking water and nutrients from the host plant like a vampire. This nightmare is called ~~field~~ swamp dodder (Cuscuta ~~campestris~~ gronovii)**. It’s the creepiest native plant I know!

See how those orange stems are reaching out, searching for its next victim?

It has no roots. It has no leaves. It has no chlorophyll. It is a complete and utter parasite, weakening its host, reducing its flowering and fruiting and making it more vulnerable to viral diseases. As soon as it has pierced its victim, it sends out more stems in search of additional victims. One seed can produce over 720 meters of stem in four months! Witches hair is another name for the dense, multi-branched, matted vines.

Doesn’t it look like witches hair? Photo credit: Scot Nelson

So you can imagine my dismay when I found this by the used-to-be-pond, wrapped around my one and only cardinal flower.

It creeped me out.
The only way to eradicate dodder is to pull up the host plant. I didn’t want to pull up my precious cardinal flower, so I cut it off at the base and hoped that was good enough. I also searched the area for other plants in dodder’s stranglehold and pulled them up. For a plant that’s supposed to be such a nightmare, I didn’t find that much. That wasn’t too reassuring, as I wasn’t sure if I just hadn’t looked hard enough or had indeed caught it early. I’ll have to revisit the area next year to see if I find more.

Of course, it’s best to pull the host plants before the dodder has gone to seed. Here you can see both flowers and developing seed capsules. (Click to enlarge)

Dodder is an annual, but it makes a lot of seed. Once the seed gets wet, it becomes sticky, and so easily travels on birds, other animals, and machinery. If it infests an agricultural field, it can drastically reduce yields. There are many species of dodder and many of those most harmful to crops are not native. However, our native dodder is considered invasive in many countries around the world.

Yes, it’s creepy.

Halloween creepy. I found the dodder and took these pictures in August, but thought it made the perfect October post for Wildflower Wednesday.

*It detects volatile chemicals released by the (potential) host plant and grows toward them. (Don’t believe me? Read this.) We use our nose to detect volatile chemicals in the air and we call it smelling. So I’m saying dodder finds its victims by smell, even though it doesn’t have a nose.

**After I wrote this post, I realized I had misidentified the species. To be fair, dodder species “are distinguished by tiny differences in their flower structure,” as the Connecticut Botanical Society points out, so it was an easy mistake to make. And Minnesota Wildflowers notes “C. gronovii appears (at least in literature) not to be the pest that some other species are capable of.” So perhaps I don’t need to be quite so scared of this plant.

Tagged as: dodder, wildflower-wednesday

About the Author

Kathy Purdy is a colchicum evangelist, converting unsuspecting gardeners into colchicophiles. She would be delighted to speak to your group about colchicums or other gardening topics. Kathy’s been writing since 4th grade, gardening since high school, and blogging since 2002.

The Newest Colchicums On The Block

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Now, the digging and dividing of perennials, the general autumn cleanup and the planting of spring bulbs are all an act of faith. One carries on before the altar of delayed gratification, until the ground freezes and you can’t do any more other than refill the bird feeder and gaze through the window, waiting for the snow. . . . Meanwhile, it helps to think of yourself as a pear tree or a tulip. You will blossom spectacularly in the spring, but only after the required period of chilling.

~Adrian Higgins in The Washington Post, November 6, 2013

Comments on this entry are closed.

Diana Studer November 1, 2018, 2:06 pm

I have a dodder in my garden. They tell me to remove it … and I peel it back from the sky down to the roots. Slowly I am winning.

Kathy Purdy November 1, 2018, 4:19 pm

I’m glad you are winning. I read that you are supposed to pull all the plants it infiltrates as well as the dodder itself, but I couldn’t bear to pull my cardinal flower. I just cut it off at ground level and hope it comes back from the roots next year–dodder-free.

Susan Farrar October 29, 2018, 9:05 am

Dodder is a parasitic plant that INITIALLY has roots as it wraps itself around its host plant, but as it sends out suckers that penetrate the host, its roots die.

Fun fact, dodder gets its species name (gronovii) from the Dutch botanist Jan Frederk Gronovius, the teacher of Linnaeus (inventor of modern systematics).

Susan Farrar
WisconsinPollinators.com

Kathy Purdy October 29, 2018, 9:45 am

I did know it initially has roots, Susan. Many of the sources I consulted said if the plant didn’t find a host within 24 hours, it died. Perhaps it was a bit of poetic license to leave out mention of the roots, but it seems for most of dodder’s life, it doesn’t have roots.

Helen at Toronto Gardens October 26, 2018, 2:20 pm

Kathy, You might be interested in reading (if you haven’t already) Daniel Chamovitz’ book What a Plant Knows. He touches on, if you’ll forgive the unintentional pun, all kinds of sensory abilities plants have – including “smell.” It’s a short, interesting read and very sciency.

Kathy Purdy October 26, 2018, 4:06 pm

Helen, I have read What a Plant Knows, and it’s what inspired me to use the verb smell to describe how dodder detects its victims.

Kerri Spooner October 26, 2018, 12:26 pm

Fascinating discovery, Kathy. Plants never cease to amaze me! Thanks for the great photos and info. Yes, the perfect post for Halloween! 🙂

Dee A Nash October 25, 2018, 10:43 am

It is really, really creepy. I hates it precious. Happy almost Halloween.~~Dee

Peter October 25, 2018, 9:10 am

Creepy dodder is perfect for Halloween. I’d never heard of this plant. Yikes! Hope you’re free of it now.

Kathy October 25, 2018, 8:13 am

Great scare Kathy! Fun post. Happy Halloween to you.

Mel October 25, 2018, 7:37 am

Ok, that is a creepy plant! I have seen it before, but didn’t know what it was. I love how plants sense the world- it’s different than mammals, but so effective and fascinating.

Lisa at Greenbow October 25, 2018, 7:19 am

I have never heard of such a plant. I will be on the lookout for it. It is a creepy plant. I have no doubt that plants can smell or how ever you want to describe it. They are so fascinating, even in their creepiness.

Judy Goodell October 24, 2018, 9:00 pm

How awful and “unearthly”-

Beth @ PlantPostings October 24, 2018, 8:41 pm

That is creepy! Yes, I remember seeing it here occasionally, but believe it or not it’s a species of special concern and critically imperiled here in Wisconsin (where it is also native). Great information and post title!

Kathy Purdy October 24, 2018, 9:21 pm

Beth, I didn’t think to check its status in NY. Turns out there is a endangered dodder in NY, smartweed dodder. https://www.acris.nynhp.org/guide.php?id=8996 It’s possible that this dodder is the one growing on my land. It certainly reminded me of smartweed. The article lists some other NY dodders: Cuscuta cephalanthi and C. coryli. Hmm. Further research is needed! Maybe I shouldn’t be ripping it out.