Every kind of plant,such as disease germ,harmful insects,weed and so on distribute on certain geographic scope,but it may spread to far place and expand distribution. 各种植物病原菌、害虫、 杂草等都 带有一定的地理分布范围，但也有 远距离传播和扩大分布的可能。Every kind of plant, such as disease germ, harmful insects , weed and so on distribute on certain geographic scope, but it may spread to far place and expand distribution. 各种植物病原菌、害虫、杂草等都 带有一定的地理分布范围，但也有 远距离传播和扩大分布的可能