IVY CAN CAUSE PROBLEMS YEAR-ROUND
We have retired to a neighborhood where we expect to spend more time
walking through woods. How do we avoid issues with poison ivy and poison
oak, and what's the difference between them? Do you have to touch the
leaves to get the blisters on your skin?
Poison ivy, which includes poison oak, is the classic outdoor pest of
the plant variety. Most botanical field guides distinguish between the
two, but the differences are subtle and do not really matter in identifying
have three leaves on each stem and a red coloration at the apex where
the three leaves connect, and both produce oils that make you itch.
claim that poison oak is more virulent than poison ivy; others say this
has not been firmly documented.
itching like crazy from exposure to either plant doesn't care that the
other one might be more virulent.
ivy can climb trees as a hairy-looking vine (usually attaching close
to the trunk), look like a shrub or be a single, simple plant. All parts
of the plant leaves, stem, fruits and roots produce oils
that can cause skin irritation in some people.
contact with the oils can cause a problem, whether from patting a dog
that has just walked through poison ivy or touching clothes that have
come in contact with the plant.
even get poison ivy internally by inhaling oil droplets that become
airborne in smoke when the plants are burned.
also get poison ivy in the winter simply by touching the leafless stem
or vine. I know of one young boy's outdoor experience gone bad after
climbing around on an oak tree with help from a big vine that turned
out to be poison ivy.
after spending thousands of hours at a research ecology lab with people
who spend time year-round in swamps, woods and streams where poison
ivy is as common as a household word, few of us ever got a serious case.
ecologists, hunters and wildlife managers who are in the woods a lot
avoid the plant without being aware they are doing so. The same would
be true of any nature enthusiast whose passion is being outdoors, whether
it be looking at birds, collecting mushrooms or simply hiking.
have no reaction when they casually brush against poison ivy, and many
are not sensitive at all. Some people spend their lives around poison
ivy without ever having a reaction.
myths and disputes about the properties of poison ivy are legion. Some
truths: You do not spread poison ivy by scratching where it itches,
despite what some people say. This misperception occurs in part because
new blisters and irritated areas can appear more than a week after exposure
to the oils. But these merely represent the lag time that can occur
after initial contact.
ivy is not contagious, and you cannot give it to someone else, except
by bringing them into contact with the oils that are on your body or
your clothes after encountering the plant.
of wildlife can eat poison ivy without being adversely affected. Dozens
of kinds of birds including bobwhite quail eat the fruits, which are
clusters of smooth, white berries that appear in late summer.
of a serious case of poison ivy contracted by a student who sorted through
the stomach contents of a recently killed deer. Among the data he recorded
for his research on the diet of deer was that they sometimes eat a lot
of poison ivy leaves.
produced by poison ivy that make us itch are not directed toward protecting
the plant from humans. The fact that some people experience dermatitis
from an encounter with the plant is purely incidental.
recognize poison ivy during your walks in the woods and enjoy the diversity
of the natural world.
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