Blog Archives (urushiol)

Urushiol lacquer table

In Japan and China, there is a tree that has a sap containing urushiol, the same oil that causes the skin rash from poison ivy, oak and sumac.

March 9, 2020 - 12:58pm
poison ivy sap

Here we have a 4-inch poison ivy vine that has been sawed through. Note how lots of sap seeps out from the bark layer. 

It is the plant sap that contains the urushiol oil that causes all the problems.

TAGS: urushiol, sap
February 11, 2020 - 12:15pm
LARGE poison ivy

As spring rolls around, poison ivy is one of the first plants to emerge. Spring leaves are usually red, but many new leaves are red, so that's not enough to go on. See our ALWAYS-NEVER criteria for deciding if a plant is poison ivy.

March 28, 2018 - 11:22am