Small-Flowered Buttercup, Littleleaf Buttercup, Kidneyleaf Crowfoot, Kidneyleaf Buttercup, Small-Flowered Crowfoot
Synonyms of Ranunculus abortivus (14) (Updated on 1-11-23 from Plants of the World Online): Ranunculus abortivus subsp. acrolasius (Fernald) B.M.Kapoor & Á.Löve (1970 publ. 1971), Ranunculus abortivus var. acrolasius Fernald (1938), Ranunculus abortivus f. coptidifolius Fernald (1942), Ranunculus abortivus var. eucyclus Fernald (1899), Ranunculus abortivus f. giganteus F.C.Gates (1930), Ranunculus abortivus var. indivisus Fernald (1938), Ranunculus abortivus var. nitidus (Walter) DC. (1824), Ranunculus abortivus f. pratensis G.Lawson (1869), Ranunculus abortivus f. sylvaticus G.Lawson (1869), Ranunculus abortivus var. typicus Fernald (1938)(not validly publ.), Ranunculus holmii Greene (1914), Ranunculus michiganensis Farw. (1916), Ranunculus nitidus Walter (1788), Ranunculus ruderalis Greene (1914)
Ranunculus abortivus L. is the accepted scientific name for this species of Buttercup. The genus and species were named and described as such by Carl von Linnaeus in the first volume of the first edition of Species Plantarum in 1753.
As of 1-11-23 when this page was last updated, Plants of the World Online lists a whopping 1,691 species in the Ranunculus genus. The genus is a member of the plant family Ranunculaceae with a total of 50 genera. Those numbers are likely to change as updates are made on POWO.
The above distribution map for Ranunculus abortivus is from Plants of the World Online. The map on the USDA Plants Database for the United States and Canada is similar.
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 SEVERAL LINKS AT THE BOTTOM OF THE PAGE FOR FURTHER READING AND TO HELP WITH A BETTER POSITIVE ID.
There are several species of Ranunculus here on the farm in west-central Missouri. Some of the species are VERY difficult to tell apart but Ranunculus abortivus is somewhat easier due to its early small flowers and kidney-shaped basal leaves. The species goes by several common names including Small-Flowered Buttercup, Littleleaf Buttercup, Kidneyleaf Buttercup, Kidneyleaf Crowfoot, and Small-Flowered Crowfoot. I am sure there are others.
Ranunculus abortivus is quite common throughout Missouri and most of North America. Like many Ranunculus species, they have an odd fibrous root system. Ranunculus abortivus prefers damp soil and can be found in low areas, along pond banks, ditches, and swampy areas. I have also found them in shady areas under trees in the spring where it stays damp. They aren’t particularly showy plants because of their small flowers.
Sometimes you will find only one 1-3 plants that have come up where you haven’t seen them before. The next thing you know, when conditions are right, there will be a multitude. It may take a year or two. You may not even notice them at first, especially if you aren’t looking for them. Their small flowers, small green leaves, and stems make them almost invisible…
The Ranunculus abortivus produces many glabrous (not hairy) stems from the base of the plant. Some of the stems grow upright while some sprawl somewhat. Sometimes a single specimen can be found.
The basal leaves are kind of round or kidney-shaped (reniform) and have long petioles (leaf stems) between the base of the leaves and the stem of the plant. The leaf margins have somewhat scalloped edges. The leaves and petioles are glabrous (not hairy).
Basal leaves are from the lowest portion of the plant, usually emerging first in the spring, and sometimes persisting during the winter with some species. The petioles of the basal leaves of R. abortivus have adaxial grooves that remind me of gutters.
The primary (center) leaves on the stem have shorter petioles and are deeply divided into three lobes with scalloped margins. The upper leaves have either very short petioles or are sessile (no petioles). The flowering stems emerge from the adaxial of the upper leaves. Leaves are three-lobed, and sometimes the lobes are lobed… This may depend on their age.
Strangely, I do not have any photographs of their lower stem leaves above the basal leaves…
The flowers are so small it is very hard to get good close-ups. I don’t know how many photos I took trying, but there were A LOT… Practice makes perfect and sometimes it seems to take several years to get a perfect shot. Most of what you see in the above photo is the fruit and it was only April 23!
Each stem terminates with 1-3 flowers. The small flowers consist of 5 yellow petals, 5 green sepals, green carpels, and 20 or more stamens emerging from the base of the pistols. The anthers and filaments are bright yellow.
Well, what can I say? A bud, a flower, and fruit…
I found the plant in the above photo (and the next two) in 2022. It’s pretty neat how the petals are arranged in a star shape.
You can see the reflexed sepals on the top flower in the above photo. Reflexed sepals (under the petals) are quite a trademark of the Ranunculus species. I am sure there are others with the same feature.
As with all Ranunculus species, they are poison so don’t go experimenting. It has already been done. Livestock avoid grazing on Ranunculus species because of the tase of the leaves. Sometimes cattle may graze on them in overgrazed pastures which can sometimes lead to death…
Oh, yeah… I read where the “receptacle” of Ranunculus abortivus is pubescent (hairy) and the receptacle on R. micranthus is hairless… To find this, I need to remove the flowers carpels, sepals, and petals. Also, the achenes (seed) of R. abortivus have a shiny surface while those of R. micranthus are dull. Hmmm… I read that on Illinois Wildflowers.
The Ranunculus abortivus is normally found in part shade in moist, fairly fertile loamy soil. They can also grow around ponds and areas where the soil has more clay.
I have enjoyed photographing and learning about the many wildflowers growing on the family farm and in other areas. The farm is 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 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 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. 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 firstname.lastname@example.org. 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)
FLORA OF NORTH AMERICA (GENUS/SPECIES)
WORLD FLORA ONLINE (GENUS/SPECIES)
USDA PLANTS DATABASE
KANSAS WILDFLOWERS AND GRASSES
FRIENDS OF THE WILDFLOWER GARDEN
NOTE: The data (figures, maps, accepted names, etc.) 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. Some of the links may use a name that is a synonym on other sites. In my opinion, Plants of the World Online by Kew is the most reliable and up-to-date plant database and they make updates on a regular basis. I make updates “at least” once a year and when I write new pages or add new photos but I do get behind. We are all a work in progress. 🙂
Other photos of Ranunculus abortivus:
I photographed this small colony next to the elm trees behind the chicken house. As you can see, it has a multitude of flowering stems. Hmmm… The above photo reminds me of R. parviflorus… Wouldn’t it be something is all the photos on this page were R. parviflorus? 🙂
A multitude of flowers for sure!
The common names Kidneyleaf Crowfoot and Small-Flowered Crowfoot come from the upper leaves.
As you can see, the leaves and stems are glabrous (hairless)…
Actually, all Ranunculus species I am trying to properly identify have these leaves…
The above photo is somewhat suspicious and very fuzzy… Ummm… Ranunculus abortivus isn’t supposed to have hair… SO, what plant did I take this photo of anyway? WELL, I do know all the photos from 4-23-20 were taken of the same colony and all within a few minutes. A similar species, Ranunculus micranthus, is VERY HAIRY. That is the problem of updating and adding photos and descriptions over the winter. I can’t go check… I am fairly certain (laughing) the photos on this page are Ranunculus abortivus. How certain is a secret. 🙂