While seining for Dobsonfly larvae, AKA hellgrammites, at a little rapids at our creek crossing, we saw these tiny flowers growing up to 5" tall, clinging to a bare rock that is always moist from the splashing water. The rock is spray painted red to indicate a safe level to cross, but even that didn't dissuade this hearty little pioneer. Based on my extensive botanical training and experience (=0) and a quick visit to INaturalist I identified it as seaside brookweed, Samolus valerand.
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| Fruit and flower- click to enlarge |
It is found across Europe, Asia, Africa and the Americas. There are a number of other common names including brookweed, thin-leaf brookweed, water cabbage, and water rose. The delicate little flowers have 5 white lobes and can occur spring through fall. Its fruits are capsules that are green and globular as seen here.
"Its inflorescence is a raceme, with small white flowers on long stalks." Wikipedia
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| Raceme flowers - Click to enlarge |
For non-botanists, like me, Oxford dictionary describes raceme as "a flower cluster with the separate flowers
attached by short equal stalks at equal distances along a central stem.
The flowers at the base of the central stem develop first." You can see this better here.
Occasional sources list it as edible when young and tender, turning bitter with age like some of us.
To me, the wonder was that it could grow on a damp rock with just moss for comfort and no soil. It can grow up to 13" tall. Again from Wikipedia, "This species is found in a variety of wet habitats, including stream banks, tidal marshes, and seeps. It can be found in both degraded and intact natural communities." This is one tough cookie!