Richard -
I lived in Escondido (north of San Diego) for some years. Moths in the
kitchen were a problem for quite some time until I found one infested
package of a cereal product tucked away in a corner of a kitchen
cupboard.
If your critters are the kind I encountered, you must take everything
out of your cupboards and examine the packages very carefully, inside
and out. Often there will be a tiny hole in the wrapper of a cereal
package, showing where a critter bored in. Often, if you look inside a
package, you will see evidence of silk threads or spider webby stuff
dangling from the sides of the package or holding bits of the contents
together. You must look very carefully. I missed one infested packet of
stuff a couple of times before I finally found and discarded it.
The more nutritious the grain products you keep in your cupboards, the
more likely they are to develop moth infestation. I don't think there's
a bug on the planet that can live in white flour. :)
Bill Dooley