The Farm...

able acid acre agriculture amounts animals atmosphere average bacteria become better bushels calcium called carbon carried cent clay climate clover combinations compared composition continuous corn crops cultivation depend drainage effective element energy especially example excess expense experiments fact farmer farming feed fertility field give grain ground growing growth half hand important inches increase indicate kind known labor land least legumes less lime limited living loam loss lower manure material matter means minerals moisture nature nearly nitrates nitrogen operations organisms period phosphorus plants plot plow possible potassium pounds practically present problem processes production profitable question rain regions reports require river rock roots Rothamsted salts sand season soil soluble supply surface TABLE tile tion treatment vegetation yield