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Walnut harvest( David Karp / For The Times )
Ever wonder where walnuts come from? Or walnut oil? Market Watch columnist David Karp offers a closer look at the process, started with a mechanized harvester at Whitney Warren Ranch, north of Sacramento. The machine gathers the walnuts, some of which still have their green hulls, from rows between the trees. A lot of debris is also picked up -- and later sorted out. More photos of the process follow.
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