The objects of constant forest and seed warehouse are a source of high quality and improved selectively forest seed. The key role in providing reproductive material is played by forest seed plantations. Evaluation of seed plantations reproductive capacity is one of the main and most important stages in the forest seed growing. The analyzing and forecasting the reproductive capacity of plantation trees is very important process. Oak is characterized by significant intervals of seed burdens. We have analyzed formation of oak reproductive organs on clonal plantations in conditions of Vinnytsia region. We have researched processes of flowering and fruiting formation of ovaries. The intensity of the reproductive processes has been studied as a part of phenological groups. The poor flowering and fruiting formation of ovaries oak during the last growing season was observed. A somewhat higher rate of formation of reproductive organs was found in intermediate phenological forms of oak. The intensity of the formation of oak generative organs on clonal plantations of the state enterprise “Vinnytsia FSRS” was very low. The average intensity of flowering oak did not exceed 0.7 points. The formation of ovaries and fruiting was almost absent and amounted to 0.2 and 0.3 points. The low formation of reproductive organs was characterized for all phenological groups. The intermediate form has a somewhat higher level of flowering (0.3 points), formation of ovaries (0.2 points) and fruiting (0.1 point). Trees with high intensity of blossom (4.0 and 5.0 points) were absent. The intermediate form had the largest share of trees (7.4%) with an intensity of 3.0 points of blossom. This form is also characterized by the highest percentage of trees with the greatest possible formation of ovaries (2.0 points) and level of fruition (1.0 points), they were respectively 4.2% and 1.3%
