Phenology describes the phenomena that happen periodically in the life of living creatures. The differences between the appearance of this phenomena result in phenology behavioral patterns. There are some cyclic phenomenas which occer periodically in the life cycle of organism which is called phenophasis. Phenophasis has different form in the various plant and manifest various behaviors. Different phenophasis are known as behavior phenological patterns. Major climate changes problems in the world have attracted attentions to the phenology and have improved studies in this field. The phonological studies are important for many applications such as silvicultural typology and afforestation, natural regeneration, livestock grazing planning, species selection for park designing and decorating. Detecting changes in Phenology of plant species receives more attention due to undergoing current climate changes studies. In this study the phenological characteristics of ten tree and shrub species has been identified, using two different methods namely descriptive and digital repeat photography. In this paper a new quantitative method based on the leaves and fruits colours change is proposed. In descriptive observations ten tree and shrub species in the campus of Isfahan University of Technology has been biweekly recorded for eight years. Digital photography of different parts of tree was accomplished for five years. The photo spectrum of the leaf and fruit of the trees were produced. In the proposed quantitative method, imaging of the plant parts (Leaf and fruit) was done in every other week intervals. Using smudge tools in Photoshop software, the colour of each part of the plant were uniformed and their RGB digits with the resolution of 2 8 for each color were assessed. Then the percentage of each colour channels was determined and the tint was achieved and their diagrams of changes during time were analyzed. This method results in an exact determination of the plant transformation. This method analyzes image series of plant parts to detect color changes; hence it provides a base to study of phenological changes in a quantitative manner. Quantitative investigation of phenology, through recording the colour of different parts of plants can be a complement for descriptive method in determining exact appearance of the phenomena. Descriptive method is the most common ways for phenology studies. Using phenological recording forms and comparing them in different species, phenological bahavior patterns were achieved. General results showes that enviromental conditions of study area cause two behavior patterns for each of flower, leaf and fruit. This also cause three patterns in fruit presence and leaf sheding. By comparison, phenological patterns find to hava four type in flower and three in leaf and phenological succession phenomena. In this method, viewpoints of the observer extremely affect the result and may cause misreporting during an observation or recording. By detecting the RGB digital number, it is easy to report the exact color and it provides a comparable bases. The RGB based reporting system can be useful in other field of studies such as pedology, geology, horticulture and so on. Keywords : Phenology, Descriptive recording, Quantitative recording, RGB