Tropical plants are strangers in most of the United States. Freezing temperatures, unknown in their native lands, force them to remain inside protective walls throughout the cold season. In south Florida, however, freezing temperatures are rare, and many tropical plants can be grown outdoors all year round. Along with the ability to grow yearround outside also comes the ability to escape. Several aroids have done just that, and a few have entrenched themselves so well among the native flora that only our historical knowledge allows us to recognize that they were brought in deliberately by man.