We often say at the admission counter to “let us know if you have any questions”, and it brightens our day when folks take us up on the offer. The other day we had a young man ask a question that we weren’t quite sure of. We enthusiastically assured him we’d look into his quandary and dedicate a Museum Monday post to the answer!
“I heard that the waterways mainland are dark because of the tannins from the cypress trees lining the banks. If there were cypress on the island, would the sound have been brown because of the tannins or no because of the connection with the ocean?”
After asking a number of knowledgeable contacts as well as some searching of our own, we are happy to say that all responses led to the same general conclusions.
We’ll take this in a few steps. We know the island had more cypress trees from early reports that were written as well as the stumps that used to be more common along the shoreline. We know Hatteras as well as the sound have shifted in size as well as salinity over the ages, which (along with logging) impacted whether cypress trees would thrive.
However, there are several places in just North Carolina where bodies of water are sounded by cypress and quite clear, such as Lake Phelps. So now we come to the questions of is the tannins in cypress causing brown waters and what makes the difference?
While tannins are found in tree bark, they’re also found in decaying plant matter. If you think about how dark the water in a deep puddle can get if it’s full of fall leaves? That’s tannins as well! This also means that it’s more likely that the waters are dark not from the cypress alone, but in areas where the water is slow moving and full of decaying vegetation. This would allow the tannins to leak, similar to how we brew tea just in a grand Mother Nature scale.
So where does this leave us? We know that post colonization, the island has shifted shape and size and the sound has shifted in its salinity content. This means that likely before European contact, the island was still in constant flux as well as the flow of water. So we can make an educated guess that if there were little coves that caught vegetation in the roots of cypress along the sound, that there could have been locations that were indeed more brown. The bending to the original question would be that it was not directly from the cypress alone; it was a cascade of different elements coming together to form the necessary circumstances in order for decaying plant matter, water movement, and cypress roots to work together. However, as most of the sound is constantly moving due to the connection with the ocean, it’s unlikely the whole of it was ever dark due to the tannins.