Bone Meal

Bones from slaughter houses, carcasses of all animals and from meat industry constitute bone meal, which is the oldest phosphatic fertilizer used. It also contains some N. Various types of bone meal are

i. Raw or untreated bone meal- Bones collected from city slaughter houses and from countryside are dried and powdered without any treatment. It contains 2.4% N and 20.0 to 25.0 % P2O5.

ii. Steamed bone meal- Bones are soaked in water and caustic soda. They are sterilized with steam and then they are dried in warm rotating oven and powdered. It contains about 27.0% P2O5 and 1.0% N. It is well suited fertilizer for acidic soil and also for long duration crops like sugarcane and banana.