P. sagittatum 3. P. arifolium Radford et al. If grasped carelessly, the skin on thumbs can also be torn. Although an annual in Pennsylvania, if P. perfoliatum enters Florida, plants might become perennial. In the U.S., the present distribution of P. perfoliatum is in temperate regions, but the weed s sub-tropical origins and its spread southward give cause for alarm.
Weeds commonly inhabit such disturbed areas.
However, this weed is also found in natural areas such as low meadows, stream banks and sites with abundant litter. Polygonum perfoliatum is sensitive to freezing. Since the plants in temperate climates do not root at the nodes, nor have a persistent rootstock, new plants must be recruited by germination. Johnson also notes that when seeds are stratified, germination seems to be less successful when temperatures are above 20 o C. Stratification involves placing seeds in moist material and storing the seeds at low temperatures in order to break dormancy of seeds. If cool temperatures are indeed required for germination, then central and south Florida may not be as threatened by movement of seed.