Valley in California. Anglo-Americans hired Mexicans and Mexican Americans to work in the region's year-round agricultural economy. Mexican farm laborers, along with African Americans, Filipino Americans, Japanese-Americans, and even Armenian Americans, Punjabi Americans, Native Hawaiians and Native Americans, were instrumental in California becoming the nation's top agricultural state. In this shift toward agricultural dominance, California relied on the cheap labor of Mexicans and Mexican Americans in a wide variety of fields. By the mid-1920s, California cotton farms were around five times larger than farms in the Deep South. This meant they needed large numbers of manual laborers, as well as technicians, since California farmers adopted tractors and picking machines at rates faster than any other region. The ability of Mexican laborers to adapt to industrial farming was crucial to the state's success. Nevertheless, even as labor unions in the 1920s grew rapidly to protect workers, some mainstream organizations, such as the AFL, were blatantly anti-Mexican. When Mexicans sought better working conditions, they often faced outright violence. Some of the decades' most infamous labor disputes occurred in Colorado. In 1927, Mexican-American coal miners participated in a bloody coal strike in Colorado, walking out under the banner of the Industrial Workers of the World. Mexican-Americans in the southeastern part of the state, particularly from the Walsenburg, Pueblo, and Trinidad areas, took leadership roles in the 1927 strike, protesting for better and safer working conditions. Some mine owners in other parts of the state retaliated against the striking miners by refusing to hire any Mexican or Mexican American in their mines. In Walsenburg and Trinidad, the mine owners went to more extreme measures to stymie the protests. Mine owners hired armed men to attack the Industrial Workers of the World's (IWW) Trinidad hall and Walsenburg branch halls. In Walsenburg, the men used a machine gun to attack the IWW hall, ultimately killing two union strikers, Salastino Martinez (age 15) and Klementz Chavez (age 41), on January 12, 1928. Josephine Roche, president of the Rocky Mountain Fuel Company, invited the United Mine Workers of America to unionize her mines, so as to meet some of the strikers' demands without alienating other mine owners, who remained strongly opposed to the IWW. LULAC and activism In 1929, the League of United Latin American Citizens (LULAC) was formed in Corpus Christi, Texas through the merging of several smaller Mexican American organizations. It was one of the nation's