Rue AnemoneThalictrum thalictroides (thuh-LICK-trum / thal-lick-TROY-deez)
False Rue AnemoneEnemion biternatum (eh-NEE-mee-un / by-ter-NAY-tum)
FamilyRanunculaceae (ruh-nung-kyoo-LAY-see-ee), the Buttercup Family

What do you call a plant that has “Meadow Rue” leaves and “Anemone” flowers?  You call it a Rue-Anemone!  We’re lucky to have not one but two native Rue-Anemones in the St. Louis area.  Their names are “Rue-Anemone” and “False Rue-Anemone”. 


The word “anemone” (pronounced “uh-NEM-uh-nee”) suggests a “wind flower”.  Good luck trying to photograph one when there’s even a slight breeze.  The Greek root “anemo” can be found in quite a few botanical terms (anemophile, anemophyte, anemotropism, anemosis, anemochore, anemoplankton).  It can also be found in everyday words such as “anemometer” (an instrument that measures wind speed) and of course “anemocracy” (a government controlled by wind or whim). 

Rue-Anemone’s botanical name (Thalictrum thalictroides) means “a Thalictrum that resembles a Thalictrum“. This strange name came about because its former botanical name was “Anemonella thalictroides“.  When the genus name “Anemonella” was later replaced with “Thalictrum“, the comical botanical name resulted.

What’s “false” about the False Rue-Anemone? Nothing. It might be better to just use the genus name “Enemion” (eh-NEE-mee-un).  It comes from the Greek word for “Anemone” and even rather sounds like it.  (Be sure to put the accent on the 2nd syllable so that it doesn’t sound like “enemy”.)

Old Family

​It’s kind of surprising that such similar plants aren’t even in the same genus.  But they’re definitely in the same family: the Buttercup Family (Ranunculaceae).  The name “Buttercup” sounds so sunshiny cheerful.  But don’t be fooled.  Buttercups weren’t born yesterday.  This is a primitive family that occupies the lowest rung on the Eudicot ladder.  If they had the chance, they’d poison us without batting a corolla.  But it’s important that we learn about them because we have no less than 23 of these fascinating species living in St. Louis.  (Click HERE to see the entire list.)

We can learn things about flower evolution by studying the flowers from plants of ancient lineage.  The Buttercup family (which has its roots way back in the Cretaceous) is a case in point. Flowers from early families tend to have simple flowers with lots of FREE (unfused) floral parts.  Their sepals and petals are FREE, they have a conspicuous ring of FREE stamens, and most distinguishing of all, they have multiple FREE ovaries.  It’s interesting to look into the flower and see the many stamens and pistils. In contrast, more modern flowers usually have only one visible ovary because they’ve largely consolidated their multiple carpels into one “syncarpous” gynoecium.  

Distinguishing Between “Thalictrum” and “Enemion”

Most people probably don’t even notice a difference between the “Rue-Anemone” and the so-called “False Rue-Anemone”.  But although the plants do look very similar, there are observable differences.  So let’s learn to distinguish between the 2 rue-anemonies instead of just lumping them together.  Here’s a story that will help us do so:


We take you now to a live debate between Thalictrum thalictroides and Enemion biternatum.  They will be debating each other for the coveted “Favorite Spring Ephemeral” award.  Our debate moderator will be the Spring Beauty herself, Claytonia, the winner of last year’s award.  She will ask both of our contestants five questions:

Claytonia: “Welcome, gentlemen, to the St. Louis ‘Favorite Spring Ephemeral’ debate.  Before we get started, I’d like to know how you want me to address you.  Mr. Thalictrum, what do you want me to call you?”

True Rue: “True Rue” has a nice ring to it.  After all, that’s what I am!  You can call this other guy “Phony Rue” or “False Rue” or whatever it is that everybody else calls him. 

Claytonia: “Mr. Enemion, is that what you’d like to be called?  False Rue?”

Mr. Five: “Actually, dear Claytonia, names and titles don’t much interest me.  Why don’t you just give me a number.  The number ‘Five’ is rather nice.”

Claytonia: “Then Five it is!”  The first question goes to you, Mr. Five.  How many petals do you have?

Mr. Five: “To be exact, dear Claytonia, neither of our genera have any petals at all.  We only have sepals that look like petals.  They’re called ‘petaloid sepals’.

True Rue: “Oh just answer her question!  You know what she means!”

Mr. Five: “I have 5 petals”

Claytonia: “True Rue, can you match his five petals?”

True Rue: “Match them?  I could do that with a leaf tied behind my stem!  If I wanted to, I could even double the number to ten!  Only five petals?  Ha!  How can this guy even sleep at night?”

Claytonia: “Here comes my second question, Mr. Five: “What colors are your petals?”

Mr. Five: “They’re white, dear Claytonia.  Please notice that W-H-I-T-E has five letters.”

Claytonia: “And you, True Rue?  What colors are your petals?”

True Rue: “Oh man, I’m embarrassed for this guy.  Only white?  What is he, a loaf of Wonder Bread?  When I want to, I can put on the most beautiful shades of pink you’ve ever seen!  You could say that I’m the proud peacock of the Rue-Anemones!”

Claytonia: “My third question, Mr. Five: “What is your favorite habitat?”

Mr. Five: “I like to live down in the lowlands where it is M-O-I-S-T and where I am fairly close to the W-A-T-E-R.  You’ll notice, dear Claytonia, that both of those words have five letters.”

Claytonia: “And you, True Rue?  What’s your favorite habitat?”

True Rue: “There’s no way you’d ever find me down there living with the riff-raff.  I’m up on the wooded slopes, up where the True Rues belong.”

Claytonia: “My fourth question, Mr. Five: “Do you live alone or with others?”

Mr. Five: “Dear Claytonia, I’m so lucky to share my life with others in a large group.  That’s G-R-O-U-P with five letters.”

True Rue: “I ain’t no groupie!  No way!  I’m a proud one-of-a-kind and I stand alone!”

Claytonia: “My fifth question, Mr. Five: “Describe to me what your leaf-tips look like.”

Mr. Five: “To be exact, dear Claytonia, the proper term would be ‘leaflets’ because…”

True Rue: “Oh just answer her question!  You blathering symplocarpus!”

Mr. Five: “I have lobes at the end of my leaflets.  That’s L-O-B-E-S, with five letters.  And you’ll notice that there’s a tiny point at the tip of each lobe.  That’s P-O-I-N-T, again with five letters.”

Claytonia: “And you, True Rue?  What do your leaflet-tips look like?”

True Rue: “Well, you’re in for a treat, honey!  Look at ‘em!  Aren’t they beauts?  Look how nice and rounded they are with those cute little indentations.  They’re like kitten paws!  What did this guy say he has?  Lobes?  Ha!  How freaky is that?  I should go out and buy him a pair of gloves.”

Mr. Five: “Oh, that would be kind of you, because I’m a pianist with the St. Louis Jazz Quartet.  That’s P-I-A-N-O with five… “

True Rue: “Now I get it!  This is a setup!  He acts so innocent, so smarmy, but everything he says has five letters in it!  He’s tricking us into remembering him!  Well try remembering this!  E-N-E-M-Y five letters!  F-A-L-S-E five letters!  Gee, I wonder how many letters ‘idiot’ has?”

Claytonia: “Gentlemen, this is getting out of hand!  Treating each other that way!  I’m afraid that now I cannot award the prize to either of you!”

True Rue: “Well, Claytonia honey, get used to it.  We Buttercups, we’re one toxic family.”

Michael Laschober

Flower Features of “True Rue” Thalictrum


Terminal umbel with 3-6 flowers; a single node of bracts subtends the flowers, sometimes in a whorl;


Calyx: 5-10 petaloid sepals which are usually white, but which may have some pale pink or lavender mixed in
Corolla: no petals


Stamens: numerous (7-30) with white filaments and yellow anthers


Ovary: numerous
Carpels: numerous (4-14) and free
Stigma: pistils bunched
Fruit: the flower’s dense green cluster of pollinated carpels will develop into 8-12 ribbed achenes.  Each beakless achene will contain a single seed.  The achenes will look like green crystals protruding from the center of some ostentatious brooch.  After the petals fall away, they’ll look like a bunch of ribbed green bananas. 

LEAF FEATURES OF “TRUE RUE”: The leaves of this plant are compound and hard to see as a unit, so let’s just deal with the delicate little leaflets instead.  Each leaflet looks like a little kitten paw.  It is palmately veined.  At its tip it tends to have 3 shallow, rounded lobes.  

HABITAT OF “TRUE RUE”: Thalictrum is usually found singly or in small groups (not in colonies) on mesic to dry wooded slopes (not usually on moist ground). 

VIDEO OF “TRUE RUE”: For a beautiful introduction to Thalictrum thalictroides, please watch this enjoyable VIDEO (7:31) by Angelyn Whitmeyer.  She communicates very effectively with a clear and simple delivery.


Flower Features of “False Rue” Enemion


Solitary flowers or loose clusters


Calyx: exactly 5 white (no pink) petaloid sepals
Corolla: no petals


Stamens: many (25-50) stamens with yellow anthers


Ovary: there are 3-6 green ovaries
Carpels: 3-6 free carpels in a whorl
Stigma: 3-6 free unfused styles and stigmas
Fruit: The fertilized carpels will develop into clusters of beaked follicles, each of which will contain 2 or more reddish-brown seeds.  A follicle contains a suture along one side that splits (dehisces) to release its mature seeds.  (This is different from the Thalictrum’s achene which has no suture and therefore cannot dehisce.)

LEAF FEATURES OF “ENEMION”:  The species epithet “biternatum” refers to the leaves being “twice ternate” or “ternate of ternate” resulting in 9 (3 x 3) leaflets.  Enemion’s leaflet has longer lobes with deeper sinuses (as compared to Thalictrum’s).  Instead of animal paws, they look more like fingers.  And those with good eyesight (or a hand lens) will notice a tiny glandular prick at the tip of every lobe.

HABITAT OF ENEMION:  Enemion is usually found in colonies on moist bottomlands of deciduous woods with rich loamy soil.


Flower-Spotter Week 02 (March 27-April 2)

Where to find “True Rue” Anemone (please protect the plants in our natural areas):

Where to find Enemion or “False Rue” Anemone (please protect the plants in our natural areas):

Please click to see a list of all our St. Louis Ranunculaceae plants.