Flowering Spurge

Euphorbia corollata

yoo-FOR-bee-uh  kor-uh-LAH-tuh

Synonyms of Euphorbia corollata (22) (Updated on 12-17-23 from Plants of the World Online): Agaloma arundelana (Bartlett) Nieuwl. (1912), Agaloma corollata (L.) Raf. (1838), Agaloma joorii (Norton) Nieuwl. (1912), Agaloma marilandica (Greene) House (1921), Agaloma olivacea (Small) Nieuwl. (1912), Euphorbia arundelana Bartlett (1911), Euphorbia corollata var. glauca Millsp. (1898), Euphorbia corollata var. grandiflora Boiss. (1862), Euphorbia corollata var. hirsuta Macnab (1835), Euphorbia corollata var. joorii Norton (1898), Euphorbia corollata var. molle Millsp. (1898), Euphorbia corollata var. subpetiolata Boiss. (1862), Euphorbia corollata var. viridiflora Farw. (1923), Euphorbia discolor Bertol. (1851)(Nom. illeg.), Euphorbia marilandica Greene (1898), Euphorbia olivacea Small (1898), Galarhoeus corollatus (L.) Haw. (1812), Tithymalopsis arundelana (Bartlett) Small (1913), Tithymalopsis corollata (L.) Klotzsch & Garcke (1859), Tithymalopsis corollata (L.) Small (1903), Tithymalopsis joorii (Norton) Small (1903), Tithymalopsis olivacea (Small) Small (1903)

Euphorbia corollata L. is the accepted scientific name for the Flowering Spurge. The species and genus were named and described by Carl von Linnaeus in the first volume of the first edition of Species Plantarum in 1753.

As of 12-17-23 when this page was last updated, Plants of the World Online lists 2,040 species of Euphorbia. The genus is a member of the plant family Euphorbiaceae with a total of 228 genera. Those numbers could change as updates are made by POWO. The number of species in the genus and genera in the family fluctuates often.

The distribution map above of Euphorbia corollata is from Plants of the World Online. Areas in green are where the species is native and purple is where it has been introduced. The map on the USDA Plants Database 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 and 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.

I first identified the Euphorbia corollata growing on the farm in 2018. They grow hit and miss mainly in the back pasture and south hayfield. I have identified four Euphorbia species on the farm and another one in a different area. It is usually easy to identify members of the genus by their weird flowers.

Euphorbia corollata is a perennial wildflower in the plant family Euphorbiaceae. This species can be found throughout Missouri and the eastern half of the United States. They can be found in just about any type of soil and prefer to grow in full sun as long as the soil is well-draining. Poor soil is OK since it reduces competition from other plants. They are very drought tolerant with their deep, spreading, branched root system and caudex.

Common names include Flowering Spurge, Prairie Baby’s Breath, Wild Spurge, and possibly others. As with other members of the plant family Euphorbiaceae, plants contain a milky sap that may cause eye and skin irritation in some people.

Plants can grow up to around 3’ tall with single or multiple stems. The stems are unbranched below the inflorescence at which point there may be a few. Stems and branches are light green yellowish green, or tan and are usually hairless (glabrous) but on rare occasions they may have short spreading hairs (pubescent). 

Stem leaves are alternate and often have whorled or opposite leaves near and in the inflorescence. At the base of the inflorescence is a whorl of 3 or more leaves. The shape of the leaves can be narrowly lanceolate, elliptic, narrowly ovate, to linear-oblong. Leaves are light grayish-green with light green midribs and margins, margins being smooth (no teeth). The leaves are normally hairless (glabrous) but can have very short spreading hairs, especially on the underside. They are commonly sessile (no petioles/leaf stems), rounded or angled toward the base, and taper to a bluntly pointed tip. Leaves grow up to 2 1/2” long and 1/2” wide.

From the top of the stems are multi-branched inflorescences (flower stems) with panicles of flowers. Missouri Plants describes the inflorescence as “3-6 primary branches usually branched 3-5 additional times, the cyathia solitary at the branch tips and branch points.” Cyathia? What is a cyathia? Hmmm… I think the cyathia is the entire flower structure including the involucral bracts that surround the reproductive organs. Wikipedia has a good page describing the cyathium (pl. cyathia) which you can go to by clicking HERE. Basically, it is a Euphorbia thing.

The panicles of flowers have a somewhat flat-headed appearance because lower flowers have longer peduncles.

OK… Explaining the flowers is also somewhat tricky, but if you look at the photo on the above Wikipedia page, maybe you’ll understand a little better. Euphorbia corollata is the only species of Euphorbia on the farm that has what resemble white petals. But, they aren’t petals… They are “petaloid appendages or bracts” (depending on what website you read descriptions from). Before I go blank again, the flowers comprise of a cup-like involucre with 5 shallow lobes around the rim. I already mentioned the 5 white petaloid appendages or bracts, but they can be notched at the tips and they could also have 5 glandular appendages at their base… Inside cyathium 10-21 staminate (male) flowers and an ovary (female part) with 3 tripartite styles. The odd thing is that the ovaries (fruit) appear to get booted out… 

Flowers are produced from May through October and attract various species of bees, small butterflies, flies, and wasps that feed on nectar and pollen. Other insects feed on the sap and leaves.

Cattle and other mammals avoid eating this plant because of its toxic latex sap. However, birds, including Wild Turkey, Greater Prairie Chicken, Bobwhite Quail, Mourning Dove, and Horned Lark eat the seeds.

Hopefully, I can take more and better photos of Euphorbia corollata in 2024. Practice makes perfect… There are more photos at the bottom of the page.

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 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 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 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
iNATURALIST
WILDFLOWER SEARCH
USDA PLANTS DATABASE
ILLINOIS WILDFLOWERS
MINNESOTA WILDFLOWERS
LADY BIRD JOHNSON WILDFLOWER CENTER
KANSAS WILDFLOWERS AND GRASSES
PFAF (PLANTS FOR A FUTURE)
GO BOTANY
USDA FOREST SERVICE
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 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 one of the most reliable and up-to-date plant databases and they make updates regularly. 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. 🙂

MORE PHOTOS…