Dandelion (Taraxacum officinale) – Its taproot is difficult to pull and its plumed seeds ride the wind. Classic dandelion puffballs each deliver 50 to 170 seeds, which can stay aloft on a four-mph breeze. One plant yields up to 15,000 seeds per season. Just one acre infested with dandelions can launch more than 240 million airborne seeds per year. Viable up to five years.