From the Calusa to early Estero Island settlers and later generations, people relied on plants and other natural resources for food, medicine, fuel, building materials, textiles, and dyes. Fire was important in Calusa culture, used for cooking and for helping carve logs into canoes. Archaeologists studying this shell mound tested soil samples for botanical remains and found 19,340 items, 90% of them charred wood, most commonly mangroves at 77%, followed by pine or oak at 21%, along with nut shells, nut meat, seeds, and grass stems. Although the Calusa diet centered on aquatic foods, evidence shows they also gathered seasonal nuts, seeds, and fruit; acorns were the main nuts found, and 91% of the seeds collected were saw palmetto seeds, many found together, suggesting seasonal gathering. Shelter also depended on plant materials, as the Calusa, Cuban fishermen at ranchos or coastal fishing camps, and late 19th century settlers used palm fronds, tree trunks, and twine made from Spanish moss to build protective structures, and records indicate that the first homesteader, Robert Gilbert, built a thatched structure on the mound site.