Most people get the rash from touching leaves, while gardening, hiking, or looking for a ball lost in the weeds.

From a tool, from a pet, from clothing: from anything that has touched any of these plants.

Using a weed eater to remove poison ivy will result in spraying your legs with poison ivy. If you are barelegged and get scratches while splattered with sap from poison ivy, you may be headed to the emergency room.

The most dangerous way to come into contact with poison ivy, oak, or sumac is by breathing smoke from a fire burning any of those plants. This happens often in California brush fires. But people have gotten very sick from breathing smoke from campfires and fireplaces where these plants are burned.