Seagrass is a plant that lives underwater, whose leaves are out of the water, but which is rooted in the sediment. Seagrass is the principal food for endangered marine herbivores, such as manatees and green sea turtles; it acts as a natural filter to help purify the water and provides a suitable environment for a wide variety of marine life. Boaters should make all possible attempts to stay within channels when unfamiliar with a waterway and make all available attempts to avoid navigating through seagrass beds, which can cause propeller scars. Navigation charts identify seagrass beds as light green or marked as "grs" on the chart. Mud trails in shallow areas are indicators of the propeller churning up the bottom and cutting seagrass roots. Boaters should avoid anchoring in seagrass areas and know their boat’s operating depth.
It is a violation of Florida law to damage sea grass beds in some areas within state waters. Some areas will have signs posted that state Aquatic Preserve. Destruction of Seagrass in Aquatic Preserves is a violation of Florida law and carries a penalty of up to $1,000.