Along our roadsides and out into fields are tangled yellowish masses that may be a few inches across or several feet wide. This curious growth is the parasitic plant commonly known as dodder.
This name apparently comes from a European language meaning "yellowness." The plant has a record of medicinal uses because it contains the substance "bergegin" or "cuscitin."
However, its greatest economic significance is in crop loss, especially in clover and alfalfa. The tiny seeds germinate on the surface of the ground, developing a rudimentary root system and a few thread-like stems two to four inches long. Sucker-like disks attach themselves to a host plant and the temporary root system dies. Then the dodder seedling is totally parasitic, taking nutrients and moisture from the host plant and eventually killing its host. The tiny seeds are long-lived so infestations may occur even where the host plants were not grown for several years.
For years this parasitic plant was only of casual interest until I was privileged to view a presentation created with high-magnification photography (similar to Terry Gregston's photo above). The slides showed the exquisite beauty of the minute blossoms and those details are obvious to me now with my ordinary hand-lens. I'd just never bothered to look!
It blooms from June until frost. Early this May, I noted small patches along North Road — now they're a three-foot-long patch, a solid orange mass.
Dodders can be propagated from broken segments. On the Internet I found a short video (PBS) showing an experiment where a fragment of dodder is placed between two plants: a tomato and a grass. With time-lapse photography, the dodder searches or "sniffs" out the better host ... the tomato.
In his "History and Folklore of North American Wildflowers," Timothy Coffee describes the legend of the Pawnee maiden who would throw a piece of dodder over her shoulder. If the parasite grew, her young man was true. Such practices apparently led to the common names of Lover's Knot and Love-vine. But most common names refer to the plant's destructive nature: Stangleweed, Scaldweed, Devil-Vine, Robber-vine.
Our plant, large-seeded dodder, has the botanical label of Cuscuta indecora. The meaning of "Cuscuta" is obscure but "indecora" means "not neat." This cosmopolitan parasite of 200 species occurs throughout the western hemisphere, and it's abundant in our area right now.blog comments powered by Disqus