09 JUN 2011 by ideonexus

 Invasive Species Between the Old and New World

Many plants new to North America first sprouted up alongside wharves and shipyards. From there they made their way inland along new roads hacked out of the wilderness, and later along canals and railroad embankments, taking up residence in any sort of disturbed soil. Native plants adapted to quiet precolonial forests and meadows gave little competition to the aggressive intruders. As Pilgrims and Puritans leveled the ancient New England forests, their floral co-colonists thrived in a landscap...
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How plants came across the sea in both directions to colonize North American and, to a lesser degree, Europe.