Seedbox, Bushy Seedbox, Bushy Waterprimrose
Synonyms of Ludwigia alternifolia (15) (Updated on 2-13-22 from Plants of the World Online): Isnardia alternifolia (L.) DC., Isnardia alternifolia var. salicifolia (Poir.) DC., Isnardia alternifolia var. uniflora (Raf.) DC., Isnardia aurantiaca DC., Ludwigia alternifolia var. linearifolia Britton, Ludwigia alternifolia var. pubescens E.J.Palmer & Steyerm., Ludwigia alternifolia var. typica Munz, Ludwigia angustifolia var. ramosissima (Walter) Poir., Ludwigia aurantiaca Raf., Ludwigia macrocarpa Michx., Ludwigia microcarpa Link, Ludwigia pruinosa Raf., Ludwigia ramosissima Walter, Ludwigia salicifolia Poir., Ludwigia uniflora Raf.
Ludwigia alternifolia L. is the accepted scientific name for this species of Ludwigia. The genus and species were described as such by Carl von Linnaeus on the first volume of the first edition of species Plantarum in 1753.
As of 2-13-22 when this page was last updated, Plants of the World Online lists 85 species in the Ludwigia genus. It is a member of the plant family Onagraceae with 22 genera. Those numbers could change as updates are made on POWO.
The distribution map for Ludwigia alternifolia is from Plants of the World Online. Areas in green are where the species is native. The map on the USDA Plants Database also includes the state of Colorado but without any county data.
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.
I found this good-sized colony of Ludwigia alternifolia in the back of the farm by the pond on September 1 in 2019 while I was wildflower hunting. The first thing that caught my attention was the square-like seed pods. There were barely any flowers to be found.
The stems of the Ludwigia alternifolia can be light green, red, brown, or even nearly white. As the plant ages, its bark will split near the base of the stems. Most of the plants had multiple branches. Ummm… The yellow flowers in the photo are not from this species… 🙂
Single yellow flowers emerge from the axils from the upper leaves on short pedicles from green bractlets that may have short hairs. The yellow flowers have 4 petals, 4 light green sepals, 4 short stamens, a pistol with a short style. The problem with finding flowers is that they only last for a single day and fall off easily.
The lance-shaped, hairless leaves grow in an alternate pattern along the stems. The leaves can grow to 4” long and 3/4” wide, are narrowly lanceolate, rounding at the tips, tapering at the base with short petioles. The leaves are light to medium green.
The stems were mostly hairless but some had a fuzzy appearance…
The odd seed capsules are nearly square the break into 4 parts to release the seeds.
I intended to hunt for the Ludwigia alternifolia earlier in the season but I was fairly busy over the summer. I have to walk through the tall grass in the hayfield to get to the back of the farm which can be very exhausting so I waited until the hay was cut.
I tried to find this species earlier in 2021 with no luck… Maybe in 2022.
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 email@example.com. I would enjoy hearing from you especially if you notice something is a bit whacky.
NOTE: Plants of the World Online is the most up-to-date database. It is very hard for some to keep with name changes these days so you may find a few discrepancies between the websites. Just be patient. Hopefully, someday they will be in harmony. 🙂
FOR FURTHER READING:
PLANTS OF THE WORLD ONLINE (GENUS/SPECIES)
INTERNATIONAL PLANT NAMES INDEX (GENUS/SPECIES)
WORLD FLORA ONLINE (GENUS/SPECIES)
MISSOURI BOTANICAL GARDEN
USDA PLANTS DATABASE
LADY BIRD JOHNSON WILDFLOWER CENTER
KANSAS WILDFLOWERS AND GRASSES
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. 🙂