Black Kow Composted Cow Manure The best-known name in composted cow manure is Black Kow. It’s odorless, weed free and rich in nitrogen-releasing bacteria. It feeds plants and builds the soil. Black Kow composted cow manure is naturally composted without chemicals or fillers. Professional landscapers, nurserymen, greenskeepers and gardners recommend it for year-round use. It makes even the poorest soil ideal for growing. Will store indefinitely. Available in 5 lb., 25 lb. and 50 lb. bags.