Milking cows is a messy, menial and low-paid job that few US workers want to do.
For years, dairy farmers - like much of America's agricultural sector - have therefore relied on immigrants.
But visas are often only available for migrants doing seasonal work such as fruit picking. And a crackdown on undocumented workers, which has led to a record number of deportations, has made it even harder for farmers to find the staff they need.
Instead, many have decided to invest hundreds of thousands of dollars in robots to milk their herd.
As one dairy farmer put it: "I have yet to have the INS (Immigration and Naturalization Service) question the Green Card of a robot."
The BBC spoke to two farmers in New York State about why they've chosen machines over migrants for now - and why they still believe comprehensive immigration reform is essential to help US agriculture in the future.
