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The leaves, compounded of five leaflets,
should sufficiently distinguish the harmless vine from the
three-leaved poison ivy, sometimes confounded with it. From
Manitoba and Mexico to the Atlantic Ocean, and even in Cuba, the
Virginia creeper rambles over thickets, fences, and walls,
ascends trees, festoons rocky woodlands, drapes our verandas,
making its way with the help of modified flower stalks that are
now branching tendrils, each branch bearing an adhesive disk at
the end. "In the course of about two days after a tendril has
arranged its branches so as to press upon any surface," says
Darwin, "its curved tips swell, become bright red, and form on
their undersides little disks or cushions with which they adhere
firmly." It is supposed that these disks secrete a cement. At any
rate, we know that they have a very tenacious hold, because often
one contracting tendril, as elastic as a steel spring, supports,
by means of these little disks, the entire weight of the branch
it lifts up.


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