Water chestnut is an emersed or floating plant. The lower leaves are submersed and are sessile, alternate, and pinnatified (cleft). The upper or floating leaves are diamond shaped with outer dentate (marginal teeth pointing out) leaf margins. The flower of Trapa natans has 4 white petals with 4 green sepals. The fruit of this plant is a nut enclosed in a thorny calyx which has 4 sharp spines.
South Carolina Law requires individuals to possess a Commercial Pesticide Applicators License in Category 5, Aquatic Pest Control, before they apply aquatic herbicides if the work is done for compensation on the property of another. A license is also required, regardless of ownership, if the application is made to an area where public access to the treated site is expected. Private swimming lakes, where the public would exposed to the treated waters, are the most obvious example of the latter requirement. On all public facilities, such as golf courses, driving ranges, subdivisions, condominium/apartment complexes and mobile home parks, applicators are required to possess a Category 5 License to apply aquatic pesticides.