No- you're thinking of the railroad builders (1860's-1870's). By 1900, when the railroads were into their big boom, most of the imported construction workers had either become citizens or given birth to the next generation, who were citizens.
I guess should have clarified that I meant the engineers, brakemen, locomotive builders, and mechanics, and not the well-known Chinese and Irish immigrants who made up the workforce building west.
I get your point but that probably wasn't the best example.