在美国危害长山核桃的瘿瘤蚜有４种，即警根瘤蚜、长山核桃根瘤蚜、美国南方长山核桃根瘤蚜和长山核桃栎叶根瘤蚜。以危害部位，虫瘿形状，性蚜体征和生物学特性将它们加以区分。其中警根瘤蚜已随苗木传入我国，在南京地区１ａ发生４代。早春阻止干母上行是比较理想的防治方法 There are 4 kinds of aphids in the United States that endanger the pecan, such as the phylloxera aphid, the rhizome aphid of the genus Chrysantha, the phylloxera of the American southern Changshan walnut, and the phylloxera aphid of the Cynanchum wallicum. They are distinguished by their harmful sites, the shape of insects, their sexual aphids, and their biological characteristics. Phylum phylloxera has been introduced into our country with seedlings, occurred in Nanjing area 1a generation 4. Early in the morning to stop the dry mother is an ideal way to control