What are the strange knobs sticking up from the ground, and what is their purpose?
These are Cypress knees, part of the root system of a Bald Cypress tree. The tree is fairly easy to recognize, even without the knees, as the base has a folded, buttressed look to it. There are many ideas for what purpose the knees serve, from support to getting air to the roots, but there is not enough evidence to support any of them at this time. My favorite part of science is all of the stuff that we don't know yet.