Term comes from wood pecker, because they normally have red hair, and whites are the only people who have red hair.
Peckerwoods do not hijack airplanes. They don't expect society to take care of them. They never demand socialist medicine. No peckerwood ever prances in a parade wearing a jock strap.
Peckerwoods mind their own business and are not a burden on society. Be nice to peckerwoods. Take a peckerwood to lunch this week!