matrix. Consequently, the harvesting of individual plants is quite simple and straightforward. Likewise, removal of any plant that may be infected with some type of pathogen is easily accomplished without risk of uprooting or contaminating nearby plants. More cost effective Aeroponic systems are more cost effective than other systems. Because of the reduced volume of solution throughput (discussed above), less water and fewer nutrients are needed in the system at any given time compared to other nutrient delivery systems. The need for substrates is also eliminated, as is the need for many moving parts . Use of seed stocks With aeroponics, the deleterious effects of seed stocks that are infected with pathogens can be minimized. As discussed above, this is due to the separation of the plants and the lack of shared growth matrix. In addition, due to the enclosed, controlled environment, aeroponics can be an ideal growth system in which to grow seed stocks that are pathogen-free. The enclosing of the growth chamber, in addition to the isolation of the plants from each other discussed above, helps to both prevent initial contamination from pathogens introduced from the external environment and minimize the spread from one plant to others of any pathogens that may exist. 21st century aeroponics Aeroponics is an improvement in artificial life support for non-damaging plant support, seed germination, environmental control and rapid unrestricted growth when compared with hydroponics and drip irrigation techniques that have been used for decades by traditional agriculturalists. Contemporary aeroponics Contemporary aeroponic techniques have been researched at NASA's research and commercialization center BioServe Space Technologies ( ) located on the campus of the University of Colorado in Boulder, Colorado. Other research includes enclosed loop system research at Ames Research Center, where scientists were studying methods of growing food crops in low gravity situations for future space colonization. In 2000, Stoner was granted a patent for an organic disease control biocontrol technology that allows for pesticide-free natural growing in an aeroponic systems. In 2004, Ed Harwood, founder of AeroFarms, invented an aeroponic system that grows lettuces on micro fleece cloth. AeroFarms, utilizing Harwood's patented aeroponic technology, is now operating the largest indoor vertical farm in the world based on annual growing capacity in Newark, New Jersey. By using aeroponic technology the farm is able to produce and sell up to two million pounds of pesticide-free leafy greens per year. Aeroponic bio-pharming Aeroponic bio-pharming is