HAMMONTON, N.J. — In this self-proclaimed "Blueberry Capital of the World" — where the little blue superfood is king and President Trump's righthand woman is a native daughter — just who will handpick the crop this summer is keeping farmer Bill Morterllite awake at night.

"I'm very worried about it. … I know a lot of other farmers are, too," said Morterllite, a third-generation blueberry grower who is preparing his farm for the growing season by cultivating the fields and installing irrigation equipment.

And he's trying to round up his labor crew for the summer, but like other farmers here he is worried about how the Trump administration's crackdown on immigrants will affect migrant workers — who primarily come from Mexico each year.

Morterllite was among only a few of the town's blueberry growers who appeared to be willing to speak out about the issue in this predominantly conservative town, where Republicans outnumber Democrats by 2-1 and Kellyanne Conway, a former Miss New Jersey Blueberry Princess, was the grand marshal of Hammonton's Christmas parade in December. Conway, a pollster who ran Trump's election campaign, is serving as counselor to the president.

There are about 120 blueberry farms statewide — and about 100 of those are clustered in Hammonton, according to agriculture officials.

And Morterllite, who operates Blueberry Bill Farms on acreage that straddles the Atlantic City Expressway, said he "took heat" from farmers and others in the community after a national television news piece last month in which he jokingly said that he hoped Trump himself would come pick the berries because the grower was anticipating having a hard time finding his usual crew of about 125 migrant laborers — who are mostly Mexican — to work on his 240-acre farm this summer.

The workers arrive by mid-June and stay until early August, completing a "really intense" six to eight weeks of harvesting and packing.

Despite its "capital" moniker, Hammonton is only the fifth-largest blueberry producer in the U.S., generating about $80 million in sales a year.

Studies from the Migration Policy Institute and the Pew Research Center indicate there are 12,000 to 15,000 undocumented immigrants living in Atlantic County and about 500,000 statewide. More than one-fifth of those — about 21 percent — come from Mexico, according to MPI.

It is unclear how many of these workers end up on farms such as those in Hammonton, but Morterllite and others say they hire only laborers who possess the proper paperwork to be allowed to work in the U.S. Farmers can be fined more than $15,000 per illegal worker.

Farmers and migrant-labor advocates say the issue involves the perception by the workers that they or their family members may be threatened by a crackdown. And, ultimately, Trump administration immigration restrictions might push at least some of Hammonton's blueberry growers out of business once and for all.

"There are so many factors that make it a difficult business to be in. This all just compounds an already difficult situation in finding people to bring in the crop," said Morterllite, who said he was tempering his comments about Trump's immigration policies, noting that the problems facing farmers are more about all the issues facing small U.S. growers — unpredictable weather, high property taxes, restrictions on pesticides, and other factors.

"All this about immigration is just the icing on the cake," Morterllite said. "I've had trouble getting ahold of some of the people who have been working here for years. Maybe they just don't want to come back to the U.S. because they are afraid."

But Denny Doyle, product specialist for Atlantic Blueberry, in Hammonton, the state's largest producer of the fruit, said labor has been "a huge, ongoing issue for years." Atlantic needs about 500 workers each summer to farm the operation's 1,000 acres and work in its packing house from which fresh and flash-frozen blueberries are shipped all over the world.

Because of the issue, Doyle said Atlantic has been working with Rutgers University in developing techniques and strategies to reduce the farm's required labor pool. But doing so takes time.

"We actively pursue new technologies that will reduce the number of workers we need each summer," Doyle said.

The technology to harvest the berries to be sold fresh and intact — instead of crushed or bruised the way they come out of a machine harvester for freezing — isn't quite ready, he said.

So for now, hand-harvesting the blueberries that are packed in pint-size containers to be sold as a fresh product — accounting for about 60 percent of what Atlantic produces — is a labor-intensive process. The remaining 40 percent of its business is in selling berries that have been frozen. "Those berries can be picked with machine harvesters," Doyle said.

But the human factor remains for most of Hammonton's mostly small, family-run blueberry farms, Morterllite said.

A record cold snap last spring resulted in a "half crop" of blueberries last summer — and unhappy pickers who had been used to earning as much as $1,000 per week hand-harvesting the fruit.

A bad growing season one year often means difficulty in getting those workers — a valuable lot because they have experience handling the produce properly — to come back for another summer. Compound the situation with anxiety about a crackdown by the U.S. Department of Homeland Security's Immigration and Customs Enforcement (ICE), and you have "a real recipe for problems," said Tim Wetherbee, chairman of the New Jersey Blueberry Industrial Advisory Council.

"It's going to have to be a wait-and-see thing," said Wetherbee, who is also sales manager for the Diamond Blueberry Farm here. "The qualified labor pool — workers who have the skill to hand-harvest the blueberries — is continually shrinking. This has been an issue for a while. We assume year to year that the workers will come back, but you can never be sure."

At Diamond Blueberry, the farm looks to employ about 500 workers to harvest and pack the crop from its 850-acre farm, Wetherbee said.

While it is unclear just how ICE may crack down on migrant laborers during this summer's growing and harvest season here — spot-checking paperwork over the summer is common practice — some immigrant advocacy groups contend the Trump administration's immigration policies are already having a negative effect.

"We've already seen problems in California and other states where people who are legally working on farms are being made to feel they are not welcome," said Johanna Calle, program coordinator for the New Jersey Alliance for Immigration Justice. "I know that there are many in these communities that are feeling afraid because they feel they are being targeted and profiled even if they have their documentation.

"A couple of summers of this sort of thing and an already shrinking labor pool could get even smaller."