据美国林务局1974年统计,美国共建立种子园4,047公顷,其中81%分布在南部。主要树种为火炬松、美国长叶松、美国红皮松和湿地松。害虫是南方松种子园种子和球果的主要破坏者。蓟马Gnophothrips fuscus对湿地松雌小球果破坏很厉害,甚至在花出现前就进入花芽,并在整个受粉期继续危害,使许多雌小球果致死。南塔克特松梢小卷蛾(Rhyacionia- According to the 1974 U.S. forest service statistics, the United States has set up 4,047 hectares of seed orchards, of which 81% are distributed in the south. The main tree species are loblolly pine, American hay pine, American pine and pine. Pests are the main spoilers of the seeds and cones of southern pine seed orchard. The thrips Gnophothrips fuscus destructed marsh cones very much and even entered the flower buds before the flowers appeared and continued to endanger the entire pollination period, killing many of the female cones. Nantucket Pinot Gracilaria (Rhyacionia-