Spatial pattern and variance of the Chinese fir anthracnose Glomerella cingualta

The spatial pattern and variance of Chinese fir anthracnose Glomerella cingualta were studied．The results show that the Chinese fir anthracnose is distributed in aggregate pattern and the environment heterogeneity is the reason for its aggregation．The aggregation decreases with the increase of stands age．The stands at 7～8 years of age is different from those at 5～6 years of age by the reason that the disease occurred severely owing to the existing mass bore and forest ill growth．Different anti-infections in different site classes for their different growt hs is the major factor for different spatial patterns of the disease，but the aggregation indexes axe nearly in different positions on slope．