If I were to cut poison ivy vine from the side of a tree, remove the outer layer of bark from the vine, and then let it dry for a period of time, would the remaining wood still have the oils that produce blisters on the skin?
I make ball point pens and would like to use the wood of the poison ivy vine, if it will be safe to use. - B.Z. -
A poison ivy pen! Novel, yes. Safe, probably not.
Most authorities we've consulted agree that the oil which causes all the trouble, urushiol, is present in all parts of the poison ivy plant (Toxicodendron radicans) except the pollen. They're also in basic agreement that the oil-bearing parts can cause trouble as much as five years after harvest. A few cite incidents where oil seems to have been preserved with ancient specimens.
We have seen occasional deviations from that agreement, to declare the inner wood cells oil-less, for instance. Yet we wouldn't want to present a gift based on that minority report, not when most people are allergic to this oil, some are hyper-sensitive, and the results could be so dreadful.
See Growing Concerns 8 for more on avoiding and treating poison ivy rash.
...poison oak - the acrid juice of this small shrub imparts a durable black dye without any addition.*
From Ramsay's History of South Carolina 1607-1808,
David Ramsay, 1858
*(Why would anyone care to know this?! Because New World plants were valuable and remaking Old World technology. As Ramsay recorded, "Dr. Bancroft... informed the writer of this history that his patent for introducing into England several dye-stuffs, gained him £5,000 per annum...")
Poison ivy (Toxicodendron radicans) is a vine that can pass for a tree because the vines that climb a tree can become thick enough in time to stand alone.
People who see old climbing vines may call them poison oak, but those plants most accurately called poison oaks are of different species. Poison oak is either the shrubby, (3') non-climbing Atlantic poison oak in the South and east, Toxicodendron pubescens, or the Pacific poison oak vine-shrub that grows in the Pacific coast States and Province, T. diversilobum).
University of Florida has an excellent resource for identifying poison ivy and its allies poison oak, poison sumac and poisonwood. Poor Florida, a place plagued with all four. How good it makes us feel to be in Michigan where we only have to look out for poison ivy (in almost any environment from sunny, sandy dunes to wet woods) and poison sumac (T. vernix, a tall shrub, growing only in wetlands).