Tree-of-heaven arrived in Pennsylvania as an ornamental in 1784; now it grows from Maine to southern California and spreads through disturbed forests
Planted as an ornamental in 1784, tree-of-heaven now grows from Maine to southern California and has infested hundreds of acres of Shenandoah forest.
We haven't written up this one. Hindustan Times - World News has the full story — the link below goes straight to it.