An engine is operated to produce exhaust emissions containing carbon nano soot therein which are injected into a solubilizing tank containing nitic acid and carbonic acid in a water solution for solubilizing the carbon nano soot as carbon nano tubes. A gas flow exiting the tank is captured such that some water and some solubilized carbon nano tubes are carried with the gas flow for subsequent delivery to a plant growing medium, either directly or by storing the water and solubilized carbon nano tubes carried with the gas flow in a tank for subsequent application. The solubilizing tank may be supported on agricultural seeding implements or sprayer implements for direct application to crop covered ground. In an irrigation system, the gas flow from the solubilizing tank is directed towards a condensing tank for subsequent application of the condensate to a plant growing medium with irrigation water.