Hypericum walteri
| Hypericum walteri | |
|---|---|
| At Tyler State Park in Smith County, Texas | |
| Scientific classification | |
| Kingdom: | Plantae | 
| Clade: | Tracheophytes | 
| Clade: | Angiosperms | 
| Clade: | Eudicots | 
| Clade: | Rosids | 
| Order: | Malpighiales | 
| Family: | Hypericaceae | 
| Genus: | Hypericum | 
| Section: | Hypericum sect. Elodea | 
| Species: | H. walteri  | 
| Binomial name | |
| Hypericum walteri J.F.Gmel.  | |
Hypericum walteri, the greater marsh St. Johnswort or Walter's marsh St. John's Wort, is a flowering plant endemic to the eastern United States, from Texas to Delaware north to Illinois. It grows along waterbodies such as lakes and streams, in marshes, and in swamp forests.