PALISADE – Producing the bright gold peaches long celebrated as Colorado’s most succulent crop increasingly requires imported workers, such as Jose Diaz of Mexico. Eyes gazing intently above a red-white-and-blue bandana for protection against dust, Diaz brings precision for pruning, savvy for selecting fruits at just the right softness, delicacy in twisting each stem ever so slightly as if the peaches were eggs, and the drive to endure 105-degree temperatures. “You have to get used to the heat,” Diaz, 20, said recently during a steamy 11-hour shift, the youngest on a crew of 65 workers from Mexico who launched this year’s harvest. They work largely out of sight in a hazy yellow glow, traipsing through rows upon rows of thickly leafed peach trees, only their scuffed boots visible from outside the orchard.