Spanish Needles

Bidens bipinnata

BY-denz  by-pin-NAY-tuh

Synonyms of Bidens bipinnata (14) (Updated on 11-29-23 from Plants of the World Online): Bidens bipinnata var. biternatoides Sherff (1930), Bidens bipinnata var. minor Memm. (1915), Bidens bipinnata var. simplicior F.Muell. (1869)(nom. nud.), Bidens cicutifolia Tausch (1836), Bidens cynapiifolia var. portoricensis (Spreng.) O.E.Schulz (1911)), Bidens decomposita Wall. ex DC. (1836), Bidens elongata Tausch (1836), Bidens fervida Colla (1834), Bidens myrrhidifolia Tausch (1836), Bidens pilosa var. bipinnata (L.) Hook.f. (1881), Bidens pilosa var. decomposita (Wall, ex DC.)Hook.f. (1881), Bidens portoricensis Spreng. (1836), Bidens wallichii DC. (1836), Kerneria bipinnata Gren. & Godr. (1850)

Bidens bipinnata L. is the accepted scientific name for this species of Bidens. Both the genus and species were named and described as such by Carl von Linnaeus in the second edition of Species Plantarum in 1753.

As of 12-29-23 when this page was last updated, Plants of the World Online lists 222 accepted species in the Bidens genus. It is a member of the plant family Asteraceae with 1,702 genera. Those numbers could change as updates are made on POWO.

The above distribution map for Bidens bipinnata is from Plants of the World Online. The map for the species on the USDA Plants Database is similar and also includes California. I used the map from POWO here because it shows the species range worldwide. Bidens bipinnata is a very versatile species covering a wide range of climates. The areas on the above map in green are where the species is native and purple is where it has been introduced.

The map on iNaturalist shows where members have made observations. Anyone can join and it is a great website to confirm and share your observations. The maps on iNaturalist are continually updated as members post new observations.

THERE ARE A FEW LINKS AT THE BOTTOM OF THE PAGE FOR FURTHER READING AND TO HELP WITH POSITIVE ID.

Bidens bipinnata is a very versatile plant as far as where they like to grow. They prefer partial shade and moist conditions in fertile loamy soil, but will grow in a variety of soils and in full sun as well. The summer of 2024 was very hot and dry and they did just fine, so they are fairly drought tolerant. You can see from the above map they can be found in many countries world in various climates. You can find them around building, in gardens and flowerbeds, vacant lots, woodland borders, along roadsides, and so on. In more sunny locations, especially in dry conditions, they may wilt but seem to recover during the night. 

There are more photos at the bottom of the page under the links…

Bidens bipinnata (Spanish Needles) grow along the fence and buildings in several areas around the yard. They don’t grow so much in the pastures compared to other wildflowers. This species may be one you prefer to call a weed…

When I was wildflower hunting on September 24 in 2023, I almost missed avoiding the Spanish Needles because they almost disappear late in the season, and among other green plants. I barely saw the seeds as I was about to walk right into them. About the only place there was to see green plants and flowers was along the south edge of the south hayfield. It gets fairly shady in this area in the early evening. It had been so dry in 2024, most of the wildflowers had fizzled out by mid-summer.

I had many Marigolds and in one bed I had to smell the leaves to tell which were Marigolds and which were Spanish Needles (or Torilis japonica-Japanese Hedge Parsley). They look a lot like Marigold seedlings.

I want to thank Pamela Trewatha of the Missouri State University in Springfield, Missouri for allowing me to share photos from their website Midwest Weeds and Wildflowers. I try to take as many good photos as I can, but they don’t always work out or I don’t take enough.

Information online says this species can grow to around 5’ tall, but here I rarely see them past 3’. The stems can be green to reddish green, normally hairless (glabrous), 4 angled (square), and branch out.

The dark green leaves are pinnatifid or pinnate giving them a ferny appearance. They are normally glabrous, but can have a few a few hairs. 

Spanish Needles are no problem until they go to seed. In fact, the plants are kind of nice looking with their dark green ferny leaves and weird yellow flowers.

Bidens bipinnata are classed with plants with opposite leaves. The Missouri State University website, Midwest Weeds and Wildflowers, describes the leaves as being finely divided (bipinnately compound). 

If you are not used to being around them, there are a few other weeds that have similar leaves. The horrible Torilis arvensis (Common Hedge Parsley) and Torilis japonica (Japanese Hedge Parsley), are “stick-tights” that have similar leaves and are probably the one I love to hate the most (and anyone else who has had to remove them from your socks, clothes, and pet fur). Another weed with similar leaves is Ambrosia artemisiifolia (Common Ragweed). While in flower, they are easily identified.

The stems terminate in a single flower head or loose clusters of heads on fairly long peduncles (flower stems). The flowers of members of the plant family Asteraceae are called heads…

The involucre consists of 7-10 outer bracts that are ascending to spreading. The margins of the bracts usually have short, spreading hairs while the outer surface is glabrous (without hairs)… The inner bracts, 8-12, are 4-9 mm long, narrowly lanceolate to narrowly narrowly lanceolate to linear and glabrous.. The chaffy bracts are narrowly oblong to linear, usually with tall white hairs at the tip. 

Involucre… The definition is a whorl or rosette of bracts surrounding an inflorescence (especially capitulum) or at the base of an umbel…

Each flower, or head, consists of 1-5 ray florets, or quite commonly they are absent (discoid). Individual flowerheads are about 1/4” across and consist of 1-5 sterile yellow ray florets (petals, corollas) or quite commonly absent (discoid). There are 12-27 disc (or disk) florets which are known as perfect flowers because they contain both male and female parts. Each disc florets has an ovary topped by a funnel-shaped corolla tube (orange) that is 5-lobed, spreading to erect, surrounded by bristles called a pappus with 2-4 teeth (awns) that are erect to spreading during fruiting. From the corolla tube emerge the stigma and style. The male parts are close to the base of the corolla tube of the female flower and consist of 5 reddish stamens, pale yellow filaments, and purplish-brown anthers that are united around the style.

The flowers attract various species of bees, files, and smaller butterflies. A number of species of caterpillars also feed on the leaves.

The seeds, called achenes, spread out like pins in a pincushion. The long narrow seeds are 4-angled, somewhat square in cross section, with 2-4 awns at the tip (which are persistent awns from the female flower) with downward pointing barbs.

Although the above photo is kind of blurry, you get the point. It is somewhat difficult to get good close-ups of the seed. I’ll keep working on it…

Now that you know the name, you can say “BIPINNATA!” every time they get you instead of using foul language. Well, maybe in addition…

The seeds are sometimes eaten by a few birds.

I will continue taking more photos of the Bidens bipinnata. I always need more photos…

I live on the family farm in Windsor, Missouri in Pettis County (Henry County is across the street, and Benton and Johnson aren’t far away). I have grown over 500 different plants and identified over 250 species of wildflowers (most have pages listed on the right side of the page). 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 few horticulturalists I contact if I cannot figure them out. Wildflowers can be variable from location to location, so that can be a bit confusing. If you see I have made an error, please let me know so I can correct what I have written.

I hope you found this page useful and be sure to check the links below for more information. They were written by experts and they have provided much more information. Some sites may not be up-to-date but they are always a work in progress. 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 thebelmontrooster@yahoo.com. I would enjoy hearing from you especially if you notice something is a bit whacky.

FOR FURTHER READING:
PLANTS OF THE WORLD ONLINE (GENUS/SPECIES)
INTERNATIONAL PLANT NAMES INDEX (GENUS/SPECIES)
TROPICOS (GENUS/SPECIES)
FLORA OF MISSOURI (GENUS/SPECIES)
FLORA OF NORTH AMERICA (GENUS/SPECIES)
WORLD FLORA ONLINE (GENUS/SPECIES)
WIKIPEDIA (GENUS/SPECIES)
DAVE’S GARDEN
MISSOURI PLANTS
MSU-MIDWEST WEEDS AND WILDFLOWERS
USDA PLANTS DATABASE
iNATURALIST
ILLINOIS WILDFLOWERS
LADY BIRD JOHNSON WILDFLOWER CENTER
KANSAS WILDFLOWERS AND GRASSES
WILDFLOWER SEARCH
PFAF (PLANTS FOR A FUTURE)

NOTE: The figures may not match on these websites. It depends on when and how they make updates and when their sources make updates. Some websites have hundreds and even many thousands of species to keep up with. Accepted scientific names change periodically and it can be hard to keep with as well. In my opinion, Plants of the World Online by Kew is one of the most reliable and up-to-date plant databases and they make updates on a regular basis. I make updates at least once a year and when I write new pages but I do get behind. We are all a work in progress. 🙂

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