Swamp Beggarticks, Three-Lobed Beggarticks, Threelobe Beggarticks, Burr Marigold
Synonyms of Bidens tripartita: Bidens tripartita var. minima Huds., Bidens tripartita var. quinqueloba C.H.An
Bidens tripartita L. is the correct and accepted name for the Swamp Beggarticks. The genus and species were named and described as such by Carl von Linnaeus in Species Plantarum, second edition, in 1753.
Accepted infraspecific names: Bidens tripartita subsp. comosa (A.Gray) A.Haines, Bidens tripartita subsp. tripartita.
The above distribution map of Bidens tripartita from Plants of the World Online, by permission, shows its native range in green and a few locations where it was introduced in purple (Kuril Island., New South Wales, and Victoria).
Plants of the World Online by Kew lists 219 species in the Bidens genus as of 1-23-20 when I am updating this page.
There are a few species of Bidens with similar characteristics as Bidens tripartita such as Bidens connata and Bidens comosa, etc. Some, such as Steyermark’s Flora of Missouri, says B. connata is a synonym of B. tripartita. All are listed as accepted scientific names on Plants of the World Online and World Flora Online. More work is being done on this group because of their similarities and variability.
There are several links at the bottom of the page for further reading.
I found a very small patch of Bidens tripartita behind the pond in the back pasture. This small area has several species of wildflowers found nowhere else on the farm. Bidens tripartita is an annual, herbaceous flowering plant in the Asteraceae family.
As I mentioned, there are several Bidens species that have a similar flower heads. Basically, the flower heads consist of 20-40 disc florets with just a few small or no ray florets (petals). The flower heads are surrounded by 4-9 green outer bracts that are long, loosely ascending, and finely toothed. There are also 7-8 yellow inner bracts that surround the flower head.
The main stems are glabrous (smooth) and the leaves grow opposite one another from leaf nodes. The leaves, which I need more photos of, are lance-shaped (lanceolate) to sort of oblong always ending in a sharp point. The leaves have toothed margins and sometimes the lower leaves may be lobed. Leaves seem to be mostly smooth (glabrous) or have fine hairs (slightly pubescent). Leaves growing on the main stem seem to have petioles (petiolate-stem between the node and base of the leaf) while those on the branches seem to be sessile (have no petioles). GEEZ!
Side branches arise from the stem above the nodes which end in 1-3 flower heads. As you can see in the above photo, the stems have a purplish color which may or may not be a characteristic of Bidens tripartita. One of the common names for Bidens connata is Purple-Stemmed Tickseed which I thought this colony could have been. Since Steyermark’s Flora of Missouri says B. connata is a synonym of B. tripartita I decided to use the latter name.
More “technical” botanical terminology can be found using the links below by clicking on World Flora Online, Missouri Plants, Midwest Weeds and Wildflowers, Minnesota Wildflowers, etc. The link to Illinois Wildflowers is about the Bidens connata (Purple-Stemmed Tickseed).
The link to Joybille Farm talk about the herbal uses of this species. It is a very good read.
I have enjoyed photographing and learning about the many wildflowers growing on the farm and other areas. I have grown over 500 different plants and most have pages listed on the right side of the blog. I am not an expert, botanist, or horticulturalist. I just like growing, photographing and writing about my experience. I rely on several websites for ID and a horticulturalist I contact if I cannot figure them out. Wildflowers can be somewhat variable from location to location, so sometimes it gets a bit confusing. If you see I have made an error, please let me know so I can correct what I have written.
I will continue with observations of this plant and take more photos in 2020.
I hope you found this page useful and be sure to check the links below for more information. They were written by experts and provide much more information. If you can, I would appreciate it if you would click on the “Like” below and leave a comment. It helps us bloggers stay motivated. You can also send an email to me at firstname.lastname@example.org. I would enjoy hearing from you.