We tried that crap here in brexit Britain. When the EU farm workers felt they weren’t welcome here, they took their labour elsewhere. And guess what? These farms didn’t hire UK citizens to do the work at higher wages, because UK citizens didn’t want these jobs. Wages didn’t suddenly go up because the naughty immigrants with their low wages had left. Seasonal farm work isn’t something most people want. Instead, crops started to rot in the fields. And the government had to make exceptions to allow the cheap foreign labour back in.