Pictured is an example of light fraction from flotation. When the soil was immersed in water, the charred plant remains floated to the top and were poured into a fine-mesh screen. Light fractions usually contain wood charcoal. Sometimes they contain nutshell fragments. Some have fragments of cultivated plants such as corn kernel or cob fragments, beans, squash rind or seeds, sunflower, and tobacco. And some have grains of wild rice, or wild plant seeds such as raspberry, nightshade, goosefoot (lambsquarters), amaranth, or many others. Plant remains can provide a great deal of information on diet, local environment, and time of year. See also flotation and heavy fraction.