 Lettuce production methods, including all of the processes from growing to sales, have become much larger in scale during the 20th century. The majority of agricultural production is done with the application of large amounts of chemicals, including fertilizers and pesticides, but organic production makes up a growing percentage of the market – a trend that began with small growers but moved to a more industrial scale. More non-heading types, mostly leaf and romaine lettuces, are also being grown. In the first years of the 21st century, bagged salad products began to hold a growing portion of the lettuce market, especially in the US. Processed from what was previously waste lettuce not considered acceptable for the fresh market, these products are packaged in a manner that makes them last longer than standard head lettuce after harvest. As of 2007, 70 percent of the lettuce production in the US came from California; in that country it ranks third in produce consumption behind tomatoes and oranges.
