This thread is amusing, although I realize that poison ivy is a serious
archaeological hazard!

Having supervised field crews for well over 30 years in regions where
poison ivy is often rampant in its growth patterns, sometimes reaching
25-30 feet or more vertically in trees with the vines being easily
sometimes 2 inches or more in diameter, I've seen hundreds of cases of
poison ivy--tongues swollen so much as to require hospitalization because
of breathing issues, testicles almost the size of tennis balls, etc.  A
treatment that works for one person may or may not work for a second
person, and doctors in the same community treat it in different ways. How
well a soap works to remove the oil seems to depend on how sensitive a
person is to the oil.  The more sensitive a person is to poison ivy the
shorter the time you have to wash off the oil.  I've also done oral
tradition research on poison ivy cures.  There is no shortage of cures,
with some persons emphatically claiming one cure is better than another or
arguing that another person's cure won't work.  With Fels Naptha and
Octagon soaps becoming harder to find in stores, perhaps archaeologists
should turn to making homemade lye soap.  It's far cheaper to make and
works identically to Fels Naptha and Octagon.  Recipes are easy to find!

Personally, I've had pretty good immunity since childhood, but as I've
gotten older I have some sensitivity, although I've been clearing about 500
linear feet of a stream bank this fall where there have been many large
vines in trees with lush clusters of the white poison ivy berries.  So far
no affect.  I will share a personal poison ivy story from my younger, naive
college professor days.  One of the first years I taught I brought a
bouquet of poison ivy in from the field and placed it in a vase in our
faculty lounge.  For my effort I heard every profane word I ever knew
existed plus some new ones to add to my vocabulary.  The room emptied of
colleagues faster than a bomb threat would likely have caused them to
move.  Needless to say, I haven't repeated my gesture.

Ronn Michael