pondgirl, i grew up backeast w/ PI and later moved to CA and live w/ PO (poison oak). the two grow somewhat differently but both treatment for symptons, and eradication of the plant itself, can be done similarly.
for treatment, we use tecnu soap. once you can identify the plant in summer and winter (w/ no leaves) and you know you may have been exposed to it, use cold water and tecnu soap topically to remove the oils......it works. it has to be used w/ in a couple hours of potential exposure.
for eradication, we wear long pants, long sleeve shirts and gloves and use pruning shears to manually remove large vines or bushes then spray 2-4D (brush be gone) on stems. clothes and tools need to be deconned aferwards. tecnu soap can be added to washing machine to dissolve oils from clothes. for mat or grass like infestations, simply spray round up or 2-4D in spring when leaves are soft. they harden as the summer wears on and require higher dosages (more product....more $$) if sprayed then.
good luck.
