Pollen dispersal and its spatial distribution in seed orchards of Cunninghamia lanceolata (LAMB.) hook

Data from three seed orchards (Chongyang, Zhangle and Laoshan) and Lintian forest of Chinese fir was used to study pollen dispersal and its spatial distribution. The results show that the pollen dispersal has its own release pattern and day-night cycle. Vertical pollen distribution is as a cluster one; Horizontal pollen distribution in seed orchards and in normal forest is a uniform distribution type. Outside seed orchards and normal forest pollen distribution is diffusible. Wind speed is the most important factor for pollen dispersal. The relationship between pollen amount and distance to a seed orchard is linear. Based on the characteristics of pollen dispersal, methods for the management of artificial pollinate during the pollen dispersal season have been developed.