When distribution of maize hybrids by maturity is based on the FAO numbers, in practice, we often get erroneous output data. This is because the earliness expression is dependent on the genetic predisposition of hybrids and the cultivation conditions. The generalization of the specific hybrid groups leads to uncontrolled errors of the estimation of an appropriate harvest time along with losses due to both digestible nutrients and fermentation of silage. Ensiling of maize at various stages of maturity has been subject of extensive research e.g.. Andrae et al. (2001), Bal et al. (1997), Cone et al. (2008), Darby a Lauer (2002), Di Marco et al. (2002), Hetta et al. (2012), Jensen et al (2005), Johnson et al. (1999), Philippeau a Michalet-Doreau (1997). Since 2012, the research project QJ1210128 is supported by the National Agency for Agricultural Research, entitled „Innovate systems of assessment of quality of feeds with emphasis on introduction of a new national evaluation system“. The main goal is a creation of an independent and unified system of assessment of maize hybrids intended for production of more valuable silage for animal nutrition during agricultural practices. The project is set so that companies offering seed maize on the Czech market can enter the research with the goal to assess the broadest range of hybrids.