The bud of two northern tree peony, introduced from Heze city to Changsha city were studied in morphological anatomy through paraffin cut section and exfoliate method to investigate its development stages. The results showed the flower bud of southward tree peony differentiated one month earlier than it did in Heze and every development stage was complete. The whole progress could be divided into seven stages： initial stage of flower bud differentiation, stage of bract primordium differentiation, sepal primordium differentiation, petal primord...
