Watch Out in the Woods (and Elsewhere)

It's time to get out in the field! But while you're looking at rocks and landscapes, are you looking out for hazardous plants? Poison oak/poison ivy (the Rhus family) is only the first of many—and the desert, where Rhus is unknown, has its own nasty guys to tend with. Familiarize yourself with my rogues' gallery of hazardous plants before you set out.
_{Poison oak, Rhus diversiloba, in its autumn colors—Geology Guide photo}