Keeping laying hens in the backyard is popular, but along with a daily supply of eggs, the hens also produce a large supply of manure. Fresh poultry manure has an unpleasant odor and will attract flies. Bedding material, such as pine shavings, is put down on the coop floor to help control odors and flies, but eventually the litter (manure and bedding material) needs to be replaced. While poultry manure can be an excellent fertilizer, it should not be used fresh. "Raw" manure can burn plants and may contain pathogens that could contaminate any plants being grown for consumption. Composting makes the manure safe to use as a fertilizer on any lawn or garden. Composting involves a process by which billions of beneficial soil organisms decompose the organic material. Simply piling up waste is not really composting. With the right proportions for materials, the process has minimal offensive odor and destroys most of the pathogens in the manure. Compost is both science and art.