Saturday, June 8, 2013

Dodder must go.

A scourge is upon my land.  A plague.  A ­­­pestilence.

Perhaps I’m overstating.  Let me backtrack.

Several years ago one of my gardening gurus, while perusing my garden, commented, “Oh, you have dodder.”

I had noticed this plant (Cuscuta sp.), twining over two native black daleas (Dalea frutescens), but was unsure of its identification. After ascertaining that it was also a native, I just let it be. Periodically, I would pull off the vines and clean up the daleas.

This year, I decided to be more proactive, and began pulling off the yellow, stringy vines earlier in the process. But the strangest thing happened. The more I pulled, the more the plant grew. Days after I spent 20 minutes pulling, the daleas were covered over again.

I looked around, and noticed small clumps of dodder in my yard, draped over prairie fleabane (Erigeron modestus).

It was time for research. After said research, it’s become crystal clear that I’ve made a terrible mistake letting dodder become established.

Dodder is a parasite.  It grows from seed, shooting up a small tendril. When the tendril encounters something to wrap around, it does so. From the website for the University of California’s Statewide Integrated Pest Management Program:

“Seedlings are dependent on carbohydrates stored in the seed (cotyledons) until they attach to a suitable host. When it contacts a host, the stem coils around the host plant and produces little structures called haustoria that penetrate the host’s vascular tissue. The dodder plant begins to extract nutrients and water from the host, and its connection to the soil withers and dries.”

Sounds kind of like a horror movie, doesn’t it?

According to Mr. Smarty Plants at the Wildflower Research Center, about 24 species of dodder live in Texas. They produce seed prolifically, and the seeds can lay dormant in the soil for 20 years.  Also, if you remove a tendril that has a haustoria, it remains viable for several days. It has lots of fun names: love vine, strangleweed, devil's-guts, goldthread, pull-down, devil's-ringlet, hellbine, hairweed, devil's-hair, and hailweed. Some of these names are very apt.

Dodder can only live on certain host plants, and apparently dalea and prairie fleabane are two of those. I don’t have many daleas. I have a whole lot of prairie fleabane.

Yesterday, I yanked up every fleabane (also some Dahlburg daisies) with dodder and tossed them in the trash. According to UC, I missed a step. I should have sealed them in plastic bags, so they won’t root elsewhere. (You know it's bad when you are supposed to seal it in plastic before discarding!)

Unfortunately, the daleas must go, also. Removing the host plants is the only way to get rid of this stuff, when it is so well established. Then I will need to replant the area with something dodder can’t use. If the dodder seedlings can’t attach to a suitable host in 5 to 10 days, they will die.

Then all I have to do is spend the next 20 years or so diligently removing new plants and their hosts.

Good grief.

Favorite spot in the garden:

The zexmenia (Wedelia texana) have taken up with the narrow-leaf dayflower (Commelina erecta var. angustifolia - I think) outside my kitchen window, and it's a very serendipitous pairing. These are volunteer natives. Aren't they lovely?


  1. I'd never heard of dodder before now, but it does sound horrible. That's kind of how I feel about agave snout weevils. The horror! Hope your preventive measures do the trick.

    1. I'm still gearing up to take out the daleas. But I've seen no additional infestations in the yard - yet.

  2. Oh my, that's awful to have to go to those lengths. I will look it up. Trailing dalea is a favorite and I would not like to have to get rid of it.

    Thanks for the heads-up.

    1. Yes, I love these plants, and they have done so well in this location. Only I can't see them for the dodder!

  3. But your dalea is some of the best ever! What a pity to lose it!

    I just went to look at my historic dodder patch and found that most of the plants have died in that area. No host, no dodder. I guess I can thank the drought. My son says he saw another patch of it out in the meadow earlier in the spring.

    And yes, the favorite spot is very pretty!

    1. I guess it's okay in moderation . . . drought might be the moderating factor! Yes, I'm sad. So sad, in fact, that I haven't pulled the daleas out, yet.

  4. Thank you for this. I didn't know about the evil dodder. Pretty sure we've had it in past springs.

  5. Gosh at first I thought you were doing a phonetic spelling of a local accent saying 'daughter'-- But no it's a kind of vampire plant! Be careful. In the movies these things can evolve quickly.

    1. Exactly my thoughts as I was reading about it! No nightmares yet, maybe tonight!