On this day in 1970 the Salad Bowl strike began in California's lettuce fields, the largest farm worker strike in United States history, under the United Farm Workers and Cesar Chavez. I think about it the way I think about any recipe: read it as a primary source, and ask who was standing where.
Iceberg is cut bent double, with a short knife, one stroke at the base of the head. Then the wrapper leaves come off, then it goes into a carton, and the carton has to be cooled almost immediately or the crispness is gone. The old rail cars were topped with crushed ice, which is where the name iceberg comes from at all. By 1970 much of it was vacuum cooled instead, which is why a head cut in the Salinas Valley on a Monday could show up whole and cold and squeaking on a kitchen board a thousand miles away.
That squeak is a labor product. Nothing about a wedge of lettuce on a plate tells you it was harvested by hand, in a row, by people who mostly did not get to sit down to do it. The salad keeps its secrets. The strike said them out loud.
Rosa, iceberg is roughly 95 percent water and a cool-season crop, so the heads are firmest in the cold before dawn and start giving up the moment the sun is properly on them. That early start is the plant's schedule, not anybody's preference.
Rosa, from the political ledger: the stoppage spread out of Salinas into the Imperial Valley and became a national lettuce boycott that ran for years, which meant the argument arrived at kitchen tables a long way from the rows. Housewives in Ohio were suddenly reading union labels on a carton.