MAY 2016 • NEBRASKAland 69
Poison ivy fruits are clusters of
tiny, pumpkinlike seeds with an off-
white rind. The fruits also contain the
chemical irritant urushiol, but that
does not stop birds from eating them.
Typically, the seeds pass through
avian digestive tracts unharmed,
making birds agents for the widespread
dispersal of poison ivy seeds.
Urushiol is far more problematic
for humans. Poison ivy rash involves
allergic dermatitis caused by contact
with the substance. Urushiol is a
colorless oil that oozes from any cut
or crushed part of the plant, including
stem and leaves. Simply brushing
against a plant may not cause a
reaction. On the other hand, a person
may develop dermatitis without ever
coming into direct contact with poison
ivy. Sticky and virtually invisible,
urushiol can be carried on the fur of
animals, garden tools, golf balls, or on
any object that has come into contact
with a broken plant. After exposure
to air, urushiol turns brownish-black,
making it easier to spot.
Urushiol is highly potent. It's
estimated that the amount needed to
make 500 people itch would cover the
FALL FOLIAGE of poison ivy at Boyer Chute National Wildlife Refuge in Washington County.
