Bird’s Foot Trefoil, Birdsfoot Deervetch, Eggs and Bacon
(Lotus corniculatus subsp. corniculatus)
Synonyms of Lotus corniculatus subsp. corniculatus (52) (Updated on 2-13-22 from Plants of the World Online): Lotus alpicola (Beck) Miniaev, Ulle & Kritzk., Lotus ambiguus Besser ex Spreng., Lotus angustifolius Gueldenst., Lotus arvensis Pers., Lotus balticus Miniaev, Lotus bracteatus Wall., Lotus callunetorum (Üksip) Miniaev, Lotus caucasicus Kuprian., Lotus colocensis Menyh., Lotus corniculatus var. alandicus Chrtková, Lotus corniculatus subsp. ambiguus (Besser ex Spreng.) Tzvelev, Lotus corniculatus var. arvensis (Pers.) Ser., Lotus corniculatus subsp. callunetorum (Üksip) Tzvelev, Lotus corniculatus f. carnosus (Pers.) Ostenf., Lotus corniculatus var. crassifolius Pers., Lotus corniculatus var. fallax Chrtková, Lotus corniculatus var. futakii Starm., Lotus corniculatus subsp. komarovii (Miniaev) Tzvelev, Lotus corniculatus var. norvegicus Chrtková, Lotus corniculatus var. posoniensis Chrtková, Lotus corniculatus subsp. ruprechtii (Miniaev) Tzvelev, Lotus corniculatus var. sativus Hyl., Lotus corniculatus var. sennenii Afr.Fern., Lotus corniculatus var. sibthorpii (Rouy) Asch. & Graebn., Lotus corniculatus var. slovacus (Chrtková) Starm., Lotus depressus Willd., Lotus dvinensis Miniaev & Ulle, Lotus forsteri Sweet, Lotus gibbus Beeke, Lotus haeupleri G.H.Loos, Lotus humifusus Willd., Lotus juzepczukii Seregin, Lotus komarovii Miniaev, Lotus norvegicus (Chrtková) Miniaev, Lotus olgae Klokov, Lotus orphanidis Ujhelyi, Lotus pentaphyllos Gilib., Lotus pilosissimus Schur, Lotus riparius Pers., Lotus rostellatus Heldr., Lotus ruprechtii Miniaev, Lotus sativus (Hyl.) Büscher & G.H.Loos, Lotus stenodon (Boiss. & Heldr.) Heldr., Lotus suberectus G.H.Loos, Lotus symmetricus Jord., Lotus tauricus Steud., Lotus tauricus Juz., Lotus tchihatchewii Boiss., Lotus uliginosus Hoffm., Lotus valdepilosus Schur, Lotus zhegulensis Klokov, Mullaghera communis Bubani
Lotus corniculatus L. is the accepted scientific name for this species. The genus and species were named and described as such by Carl von Linnaeus in the second volume of the first edition of Species Plantarum in 1753.
Accepted Infraspecific names (5) (Updated on 2-13-22 from Plants of the World Online): Lotus corniculatus subsp. afghanicus Chrtková, *Lotus corniculatus subsp. corniculatus (autonym), Lotus corniculatus subsp. delortii (Timb.-Lagr.) Nyman, Lotus corniculatus subsp. fruticosus Chrtková, Lotus corniculatus subsp. preslii (Ten.) P.Fourn. *When infraspecific taxon are named, an autonym (“type-specimen”) is automatically generated whose description is closest to the (original) species. All have their own list of synonyms…
As of 2-13-22 when this page was last updated, Plants of the World Online lists 119 species in the Lotus genus. It is a member of the plant family Fabaceae with 773 genera. Those numbers could change as updates are made by POWO.
The above distribution map of Lotus corniculatus is from Plants of the World Online. It shows where the species is naive in green, purple where it has been introduced, and gold where it is doubtful. POWO gets their maps for North America from Flora of North America. The plant family Fabaceae is not included in Flora of North America “yet” when I uploaded this map. They are working on it and it will be released soon, then POWO will update their maps. I mainly wanted to use this map to show where the species is native. We are all a work in progress. They have come a LONG WAY…
The above distribution map for Lotus corniculatus is from the USDA Plants Database map for the United States and Canada. All areas in blue show where the species 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 SEVERAL LINKS AT THE BOTTOM OF THE PAGE FOR FURTHER READING AND TO HELP WITH A BETTER PLANT ID.
I always wondered what those yellow flowers were growing along the highways and backroads were. They grow right along the pavement or in the gravel. In the summer of 2019 when I was working on a friend’s farm, I noticed there were several wildflower species there that weren’t on my farm, including a small patch of Lotus corniculatus. Guess where they were growing? Along the gravel drive going to his back pasture… Anyway, I took photos and identified them as Lotus corniculatus. Common names include Bird’s Foot Trefoil, Birdsfoot Deervetch, Eggs and Bacon, and likely others.
Although there are five accepted subspecies of Lotus corniculatus, only the “original” species is found in North America. The autonym, Lotus corniculatus subsp. corniculatus isn’t really a subspecies per say. That may be hard to understand, but you just have to go with it. It will come to you eventually. The other four are subspecies and they all have a limited range in Europe (rather Eurasia).
Lotus corniculatus is an herbaceous perennial species that grows from 6” to 2’ tall from a woody taproot. They are a European native that has made itself quite at home throughout most of North America. The species was originally brought to the United States for erosion control and planted along highways, which is why they are a common sight there. It is also planted in pastures and hayfields due to its high protein content.
Some websites say Lotus corniculatus poses no threat to native species, while others say is is very aggressive and has above average potential to become invasive. Although it does well in full to part shade, is quite adaptable to poor soil, and has been planted in waste areas to rejuvenate the soil, it may not invade well established natural habitats. Personally, I have only seen this species growing along highways and backroads and the one very small patch in my friend’s pasture (in the gravel where only other “weeds” and very tough grass will grow).
Lotus corniculatus is definitely a showy plant with its “umbels” of bright yellow flowers. Its odd so-called trifoliate leaves, with an extra pair of leaves, are another distinguishing feature of Bird’s Foot Trefoil.
On July 22 in 2021 I decided it was time I went out on a few back roads south of town to get photos. I had noticed there were a few species I needed photos of besides the Lotus corniculatus.
The stems of Lotus corniculatus are round and are called “spreading to ascending”, forming loose mounds. The stems can be smooth (glabrous) or have a few odd hairs (pubescent), usually toward the tips.
The compound leaves grow in an alternate manner along the stems. They are usually described as “trifoliate”, but in this case there is an extra pair of leaves at the base of their short petioles (leaf stalk) where they grow from the stem (at the leaf node). There are also inconspicuous stipules at the base of the petioles, appearing as gland-like dots. The leaves and petioles are glabrous (hairless) to minutely pubescent (hairy).
The flowers… Well, I will give you the shortest version I can without confusing myself… Missouri Plants describes the inflorescence (flowering structure) as being “axillary, umbellate to loosely headlike clusters of 3-8 flowers.” Other websites say as many as 12.
In 2022 I will attempt to take some better close-ups so I can describe the flowers better. They are kind of complicated but I will do the best I can. The flowers are papilionaceous (pea-like) with 5 petals. The standard is the largest petal, the keel is made up of two petals, and the two lateral petals are the wings. The wings are boat-shaped, curve upward, and fused above the midpoint. The yellow flowers are surrounded by green calyces that are sharply pointed. There are 10 stamens with alternating long and short filaments. 9 of the filaments are fused and one of the stamens is filament free. The yellow flowers may turn a reddish color with age.
The flowering period is from May-September and the main pollinators are long-tongued bees.
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 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)
WORLD FLORA ONLINE (GENUS/SPECIES)
THE FRIENDS OF THE WILDFLOWER GARDEN
MSU-MIDWEST WEEDS AND WILDFLOWERS
USDA PLANTS DATABASE
KANSAS WILDFLOWERS AND GRASSES
PFAF (PLANTS FOR A FUTURE)
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. 🙂