Now, I have no idea how these were grown and really, the location tells me it was conventional, but I'm not going to "kick a gift horse in the mouth" and turn down free food. We actually ended up slicing them and putting them in the food dehydrator and then pulverized them in the blender. We had about 8 of this size and ended up with about 1 1/2 cups of onion powder. NOTE: Do NOT dehydrate onions in the house. This is a job best left for outside - plus, if it's warm enough, the ambient temperature will help it along as well.
Thinking about gleaning? Check out some other sites, but make sure you follow common courtesy - take only what you will use! Leave some for others to glean as well. This is not the time to be stock piling.