Have there been any studies on 'surf balls'? (not related to surfing)
These surf or beach balls are made of plant material throughout the structure. They form by wave action along beaches. As the naturalist at Wilderness State Park, the campers and I discovered over 30 of these balls along the beach the summer of 2017.  In previous summers we had found 0. Lake Michigan and Lake Huron were at record levels during the summer of 2017, the highest since 1998. This may explain the formation of these grass balls in abundance. We found some of the balls still in the water, in a depression, just offshore. Others were rolling in and out with the waves. Some had been deposited on the shore and were filled with large quantities of sand. I shook out nearly a cup of sand from one ball. I dissected one surf ball and found predominantly roots and grasses. I will continue to investigate the species of plants that form these curious creations and try to discover the secret to their formation