Automation can fix this moving forward but ultimately the lost crops are a result of a bad business decision by the farmers to rely on an an undocumented underpaid labor force without thinking there would ever be any repercussions.
https://www.cbsnews.com/news/despite-economy-americans-dont-...
Most americans are unwilling to work on farms, even at the heights of the recent recession.
No sane person with any other options would take that trade
at the wages offered by farm owners!!! This is very similar to arguments trotted out in support of shitty H1B jobs. You want workers for your jobs? Increase the wages. Increased wages will make you raise the prices for your customers? Do so, or find the efficiencies in your business. Increased wages might drive consumers to produce grown in foreign countries? Have appropriate trade agreements protecting vital industries like agriculture, similar to what we have for defense (and after all, trade agreements are not a suicide pact (TM)).
Possibly, but it may also depend on how much the current political climate could have been foreseen. The reality is that it's been the status quo for decades, and there's been clemency for illegal immigrants that grants citizenship in the past.
Ultimately while it ended up being a bad decision, it might have been one that was considered an extremely safe one until everything changed. Sort of like buying a car with the assumption you'll still have a job next year. If you needed a car then it might have been good decision until all of a sudden it really wasn't.
This is an area for regulation (no one raised an eye when they got cheap labor) and economic incentives (NAFTA f'd over Central American economies, commodities market manipulation causes prices to skyrocket in developing markets - both causing mass migrations).