Study on phonological and growth characteristics of different poplar clones (Populus euramericana (Dode) Guinier) in Guilan province

Collection research design established with 64 clones of poplar at climatic condition of poplar research station in 1983. They are planted in distance 5 meter in row. This design find out after two nation design as collection of different poplar clones and selection nursery establishment. Factors of phenomena like open catkin، flowers، capsule of seeds and leaves falling were studied every year. Results showed that Populus chopita was sooner than the other clones and P. e. 94/57 was late for catkin appearance. Physiological activities start with appearance leaves that P. e. 488 clone was sooner and P. agresgrandis was latest of them. Seed dispersal was started in P. e. 488 clone sooner and P. e. costanzo was late. Amount of diameter growth in P. e. triplo clone with diameter average 24/73 cm and P. e. riminii clone with15/81cm were most and least respectively. Height growth in P. e. 45/51 and P. e. agresgrandis with 28. 65 and 14. 4 m were most and least respectively.