Rick Shade, the farmer, only has 25 of the 50 needed workers for the peak season, putting him in a bind at a critical time for his business.

Farm labor shortages, especially in California, the nation’s leading agricultural state, are widespread, according to news reports. In California, 55% of farmers said they didn’t have enough workers, a survey by the California Farm Bureau Federation in 2017 found.

Immigration policies, an aging population of current workers, and an apparent reluctance from Americans to take farm jobs are just some of the complications.

The slowdown in migrants crossing the border began in 2005 and continued through 2014, Los Angeles Times said. While labor shortage began with a tightening of the border under President Barack Obama, the latest push under President Trump is sparking fear in farm communities and creating chilling effect on recruiting farm labor.

From 2013 to 2014, nearly 47% of agricultural workers were undocumented, according to the National Agricultural Workers Survey. Another 31% were citizens while 22% had legal papers to work.

In California, the ratio of undocumented immigrants in the farm industry is even higher. One and a half million out of 2 million workers are illegal, according to Western Growers Association president Tom Nassif, who supported Trump for president.

To attract workers, farmers are raising wages to well above the minimum wage, which in California is $11 per hour, especially in higher cost places like Napa, Calif. Farmers are also increasingly paying for H-2A visas for guest workers.

Last year, California growers recruited a record 14,252 foreign workers under H-2A visas, according to the Los Angeles Times. However, some growers say that the visa process is too slow and costly because farmers must pay for transportation, meals and housing for H-2A workers.

Despite wage increases and some growers providing health insurance and 401(k)s, recruiting native-born workers remains difficult. “Nine in 10 agriculture workers in California are still foreign born, and more than half are undocumented, according to a federal survey,” the Los Angeles Times said.

A report by the Center for Global Development in 2013 examined the troubles encountered by the North Carolina Growers Association, which connects farmers in North Carolina with workers. Due to regulations, the NCGA must show that no native workers were willing to take the jobs before they’re able to use workers who have H-2A visas, the Washington Post said.

“In 2011, 245 people were hired out of 268 referred, but only 163 (66.5 percent) of the hired applicants actually showed up to the first day of work. Worse, only seven lasted to the end of the growing season,” the Post reported.

During that year, there were nearly 500,000 unemployed people in North Carolina, showing the difficulty in getting residents to work on farms.

However, George Borjas, a Harvard University economist who favors more strict immigration, told the Los Angeles Times that wages are still too low for American workers to accept farm jobs.

Beyond raising wages to lure more American workers, or recruiting H-2A visa workers, farmers are also switching from human labor-intensive crops like grapes, tomatoes, and avocados. Instead, they are focusing more on crops that require fewer workers like almonds or crops that can be harvested using automation like some lettuce, or moving growing to Mexico as is the case with asparagus.

“We’ve shifted away from the most labor-intensive crops – so things like vine-ripe tomatoes, we no longer grow anymore,” Oxnard, Calif.-based farmer Tom Deardorff told NPR. “We’ve also shifted a large amount of our production down into Mexico.”