<P> About half the settlers coming to California after 1846 came by the wagon trains on the California Trail (a trip of about 140--160 days). The other half came by sea via paddle steamers going to and from the Isthmus of Panama or Nicaragua (about a 40 + day trip). The building of the Panama Railroad in 1855 made this a much more used route especially for passengers . The other main sailing ship route was going around Cape Horn, about a 120 - day (via Clippers) or 200 day trip by regular sailing ship . Nearly all freight to California till 1869 took this long route around South America--shipping by ship has nearly always been relatively slow but cheap . Overland shipping was too difficult and took too long for nearly all cargo . The First Transcontinental Telegraph replaced the Pony Express in 1861 and established the first rapid communication with the east coast . The First Transcontinental Railroad was completed across the future states of Nebraska, Wyoming, Utah and the new states of Nevada (est. 1864) and California in 1869 and cut this trip to about 7 days . This rail link tied California and the rest of the Pacific states firmly into the union and led to much more rapid and profitable commerce between the states . In 1886 the first refrigerated cars on the Southern Pacific Railroad entered operation . The loading of such cars with oranges, at Los Angeles on February 14, 1886, started an economic boom in the citrus industry of Southern California, by making deliveries of perishable fruits and vegetables to the eastern United States possible . </P> <P> Early farming in the state was primarily concentrated near the coast, and the Sacramento--San Joaquin River Delta in the Central Valley . Winter wheat was an early crop that grew well without irrigation if planted in the fall and harvested in the spring . By the 1880s extensive grape fields for producing wine were being planted in many areas in California . Many of the vine stock originally came from France and other parts of Europe . Starting in the late 1880s, Chinese workers and other laborers were used to construct hundreds of miles of levees throughout the Sacramento--San Joaquin River Delta's waterways in an effort to control flooding, reclaim and preserve flooded land that could be converted into farmland . This area now often grows extensive rice crops . Subsequent irrigation projects have brought many more parts of the Central Valley into productive agriculture use . The Central Valley Project, formed in 1935 to redistribute water from northern California to the Central valley and Southern California helped develop more of the Central Valley . Water for agricultural and municipal purposes was captured in the spring from snow melt in the Sierra Nevada (U.S.) and stored for later irrigation use with an extensive system of dams and canals . The even larger California State Water Project was formed in the 1950s, consisting of the California Aqueduct and its ancillary dams . The California Aqueduct, developed at the cost of several billion dollars, helps store and transport water from the Feather River Basin to agricultural and municipal users statewide . The Colorado River Aqueduct delivers water from the Colorado River to the Imperial Valley of California area and since 1905 the Los Angeles Aqueduct delivers water over from the Owens Valley to the city of Los Angeles . One of the state's most acute problems is its appetite for water . In the extensive fields of the Imperial Valley, irrigation is facilitated in part by the All - American Canal--part of the Colorado River Aqueduct project . Cutbacks in federally funded water projects in the 1970s and 80s led many cities to begin buying water from areas with a surplus; but political problems associated with water distribution continue . Ongoing challenges to develop a long - term plan to end surplus water withdrawals from the Colorado led the federal government to stop the release of surplus river water to the state in 2003 . </P> <P> Agriculture is one of the prominent elements of the state's economy: California leads the nation in the production of fruits, vegetables, wines and nuts . The state's most valuable crops are cannabis, nuts, grapes, cotton, flowers, and oranges . California produces the major share of U.S. domestic wine . Dairy products contribute the single largest share of farm income . California's farms are highly productive as a result of good soil, a long growing season, the use of modern agricultural methods and extensive irrigation . Irrigation is critical since the long dry summers would not allow most crops to grow here--California Indians had almost no agriculture because of this . Extensive and expensive irrigation systems including furrow "gravity" irrigation, sprinkler and drip irrigation systems have been developed to supply the extensive irrigation needs of California . Illegal immigration to the United States has been traditionally drawn to the state, in part, because corporations face intense pressure to control labor costs by using illegal means to harvest California's extensive crops . </P> <Table> <Tr> <Td_colspan="6"> Top publicly traded companies in California for 2011 according to revenues with State and U.S. rankings </Td> </Tr> <Tr> <Td> State </Td> <Td> </Td> <Td> Corporation </Td> <Td> </Td> <Td> US </Td> </Tr> <Tr> <Td> </Td> <Td> </Td> <Td> Chevron </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> </Td> <Td> </Td> <Td> Hewlett - Packard </Td> <Td> </Td> <Td> 11 </Td> </Tr> <Tr> <Td> </Td> <Td> </Td> <Td> McKesson </Td> <Td> </Td> <Td> 15 </Td> </Tr> <Tr> <Td> </Td> <Td> </Td> <Td> Wells Fargo </Td> <Td> </Td> <Td> 23 </Td> </Tr> <Tr> <Td> 5 </Td> <Td> </Td> <Td> Apple </Td> <Td> </Td> <Td> 35 </Td> </Tr> <Tr> <Td> 6 </Td> <Td> </Td> <Td> Intel </Td> <Td> </Td> <Td> 56 </Td> </Tr> <Tr> <Td> 7 </Td> <Td> </Td> <Td> Safeway </Td> <Td> </Td> <Td> 60 </Td> </Tr> <Tr> <Td> 8 </Td> <Td> </Td> <Td> Cisco </Td> <Td> </Td> <Td> 62 </Td> </Tr> <Tr> <Td> 9 </Td> <Td> </Td> <Td> Walt Disney </Td> <Td> </Td> <Td> 65 </Td> </Tr> <Tr> <Td> 10 </Td> <Td> </Td> <Td> Northrop Grumman </Td> <Td> </Td> <Td> 72 </Td> </Tr> <Tr> <Td> 11 </Td> <Td> </Td> <Td> Ingram Micro </Td> <Td> </Td> <Td> 75 </Td> </Tr> <Tr> <Td> 12 </Td> <Td> </Td> <Td> Google </Td> <Td> </Td> <Td> 92 </Td> </Tr> <Tr> <Td> 13 </Td> <Td> </Td> <Td> Oracle </Td> <Td> </Td> <Td> 96 </Td> </Tr> <Tr> <Td> 14 </Td> <Td> </Td> <Td> DirecTV </Td> <Td> </Td> <Td> 110 </Td> </Tr> <Tr> <Td> 16 </Td> <Td> </Td> <Td> Amgen </Td> <Td> </Td> <Td> 163 </Td> </Tr> <Tr> <Td> 17 </Td> <Td> </Td> <Td> Gap </Td> <Td> </Td> <Td> 167 </Td> </Tr> <Tr> <Td> 18 </Td> <Td> </Td> <Td> PG&E </Td> <Td> </Td> <Td> 177 </Td> </Tr> <Tr> <Td> 19 </Td> <Td> </Td> <Td> Health Net </Td> <Td> </Td> <Td> 179 </Td> </Tr> <Tr> <Td> 20 </Td> <Td> </Td> <Td> Edison International </Td> <Td> </Td> <Td> 198 </Td> </Tr> <Tr> <Td> 21 </Td> <Td> </Td> <Td> Qualcomm </Td> <Td> </Td> <Td> 222 </Td> </Tr> <Tr> <Td> 22 </Td> <Td> </Td> <Td> Jacobs Engineering </Td> <Td> </Td> <Td> 250 </Td> </Tr> <Tr> <Td> 23 </Td> <Td> </Td> <Td> Western Digital </Td> <Td> </Td> <Td> 251 </Td> </Tr> <Tr> <Td> 24 </Td> <Td> </Td> <Td> Applied Materials </Td> <Td> </Td> <Td> 259 </Td> </Tr> <Tr> <Td> 25 </Td> <Td> </Td> <Td> URS </Td> <Td> </Td> <Td> 267 </Td> </Tr> <Tr> <Td> 26 </Td> <Td> </Td> <Td> eBay </Td> <Td> </Td> <Td> 269 </Td> </Tr> <Tr> <Td> 27 </Td> <Td> </Td> <Td> Sempra Energy </Td> <Td> </Td> <Td> 274 </Td> </Tr> <Tr> <Td> 28 </Td> <Td> </Td> <Td> Synnex </Td> <Td> </Td> <Td> 281 </Td> </Tr> <Tr> <Td> 29 </Td> <Td> </Td> <Td> Visa </Td> <Td> </Td> <Td> 297 </Td> </Tr> <Tr> <Td> 30 </Td> <Td> </Td> <Td> Gilead Sciences </Td> <Td> </Td> <Td> 299 </Td> </Tr> <Tr> <Td_colspan="5"> Further information: List of California companies <P> Source: Fortune </P> </Td> </Tr> </Table>

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