It was studied the mechanism of adaptation of different aged trees (2, 10 and 20 years old), representatives of aborigen flora, grown from the seeds of Yerevan reproduction in the conditions of Yerevan (1250 m below sea level) and Sevan (2000 m below sea level) botanic gardens.
   It is found out that the high-mountainous conditions, being extremal for many trees brought in from low-lying, during the time become normal in the result of energetic adaptation in early age.