HAMMONTON — Atlantic Blueberry Co.’s 1,100 acres of blueberry plants will be hand-picked three times this season by migrant labor because blueberries on the same plant ripen at different times, General Manager Denny Doyle said.

Toward the end of the season, in late July, a machine harvester will go over every plant, getting the last of the crop. But the machines, which send long, vibrating mechanical fingers through the bushes to shake off the fruit, must be used sparingly. They often damage the plants and fruit, said Nicholi Vorsa, director of Rutgers University’s Philip E. Marucci Center for Blueberry and Cranberry Research and Extension in Chatsworth.

Since 2000, Vorsa has been leading the research to breed blueberry varieties that can better handle the stress of mechanical harvesting, to help farmers save money and avoid dependence on an uneven stream of immigrant labor.

New Jersey is still tops in the nation for growing blueberries for the fresh market, even though many new states, such as Oregon and Washington, have entered the industry in the past decade. New Jersey’s blueberry farms grow 43 million pounds per year for the fresh market, and just 8.5 million for the processed market, on about 8,000 acres.

But in total pounds of berries grown, including for the processed industry, New Jersey is sixth behind Maine (which sells mostly wild berries), Michigan, Oregon, Washington and Georgia, according to the U.S. Department of Agriculture, or USDA.

It’s an $80 million industry in New Jersey. Only the industries in California, Michigan, Oregon, Georgia and Washington make more money.

Until about the 1970s, blueberries were picked by high school students and Puerto Rican laborers. Then Asians displaced by the Vietnam War came through, followed more recently by Mexican workers, Vorsa said.

Atlantic Blueberry is providing field space and labor to grow 500 of the most promising new varieties created at the Marucci center. They grow side by side on several acres on Weymouth Road. It took years to select them from thousands of crosses of different varieties and species. Now they must be grown in the field and get big enough to test with the harvesters, Vorsa said.

The Marucci center is charged with helping the state’s blueberry and cranberry industries through research. As more states have entered the blueberry industry, that means helping growers adapt to be competitive.

“It used to be three states,” Doyle said of New Jersey, North Carolina and Michigan. “Now it’s 33.”

Atlantic Blueberry’s two huge farms — the other is in Hamilton Township on the Black Horse Pike — will have about 800 people working at the height of the harvest in June and July. They are mostly pickers, Doyle said.

“It’s expensive,” said Doyle of the human labor involved on a recent tour of Atlantic Blueberry’s farm on Weymouth Road in Hammonton. Each year farmers must compete with other farms along the Eastern Seaboard for labor, never knowing until the last minute if last year’s labor pool will return.

With the development of the Georgia blueberry industry, and farms growing later-fruiting varieties there, New Jersey farms must find a way to lure workers north.

“We have a great return record here,” Doyle said. “About 90 percent of our workers come back year after year.”

But if he could rely on machines to pick, his whole operation would be more efficient and economical, he said.

Politics and immigration policy can also restrict growers’ access to labor, Vorsa said.

“There would be great advantages if we would use mechanical means to harvest for the fresh market,” the researcher said.

The trick is, varieties can’t be selected just for the one quality of machine harvestability. They still must also produce a lot of fruit, taste great, be self-pollinating, store and travel well, and have many other necessary qualities to make them a good market plant, Vorsa said.

Any one weak link and the plant can’t be used, Vorsa said.

Dr. Jennifer Cicalese works in the greenhouses at Marucci, hand-pollinating plants to control breeding. She is crossing a Florida species with the Northern highbush blueberry, commonly grown in South Jersey.

Cicalese has been working here for 10 years, and her job requires incredible organization skills, to be able to keep track of which plants are crosses of which varieties and to note each of the offsprings’ characteristics.

“We have gone through 8,000 to 9,000 varieties since 2002,” Vorsa said.

It’s a long-term project not likely to pay off for many more years, he said.

“You need to grow the plant up,” he said. “It’s a long process.”

The Marucci center is a substation of the New Jersey Agricultural Experiment Station of Rutgers University. It has been operating since 1962 on acres of labratory buildings, greenhouses and experimental fields on Lake Oswego Road here, in cooperation with the United States Department of Agriculture-Agricultural Research Service.

Marucci’s goals are to advance the blueberry and cranberry industries through basic and applied research; minimize the use of pesticides in growing them; identify beneficial health properties in the fruits; and investigate causes and controls of diseases that affect the crops.

The first center opened as a cranberry research facility in Whitesbog in 1918 and later expanded to include blueberries as the market for the newly developed fruit emerged.

Blueberries were first developed for market in Whitesbog, Burlington County, in 1916. They became the basis for an entirely new agricultural industry, able to use acid soils previously considered agriculturally worthless, according to the Marucci center’s website.

The center has developed blueberry varieties that are grown all over North America, Vorsa said. Rutgers and USDA cooperative research there cultivated the first highbush blueberry varieties and others, such as Duke, developed in the fields of Atlantic Blueberry in Hammonton and named after one of its founders, S. Arthur “Duke” Galletta, who died at age 85 in 2000. It’s now one of the most popular varieties planted, Vorsa said.

The center has also developed control methods for insect pests, such as the blueberry maggot and leafhoppers, both of which transmit disease.

The center’s work explained the crucial role bees play in pollinating blueberries and cranberries, and it created techniques for applying fungicides to both crops with minimal disturbance to the environment, according to its website.

Contact Michelle Brunetti Post:

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