A proposed model of the interactions between DNA methylation and vernalization pathway genes during vernalization-induced floral development. The short days and low temperature of fall and winter induce increased DNA methylation, which upregulates genes involved in the vernalization pathway, including VIN3, SWN, VRN1(AP1), VRT2, and AGL20. This methylation increase also promoted the floral primordium initiation and development in orchardgrass. The longer days and warmer temperatures of spring further promoted the floral development and flowering of orchardgrass. The plant images were digitally extracted from the original images, which were taken with a camera.