Dark days for mushroom growers Mold: In the mushroom country of southeastern Pennsylvania, a stubborn green mold is destroying as much as half of the crop and defying every effort to eradicate it.

July 27, 1996|By Peter Jensen | Peter Jensen,SUN STAFF

OXFORD, Penn. -- In the cool, damp darkness, the green villain lurks.

Amid the snowy-white abundance of Jamie Ciarrocchi's mushroom houses, the many green-tinged patches of barren soil mark the enemy's turf.

Green defines life on a sunlit field, but it signals dark days for the windowless world of mushroom cultivation.

The dreaded Trichoderma harzianum, commonly known as green mold, is ravaging another crop.

"It is very aggressive," said Ciarrocchi, 37, a third-generation southeastern Pennsylvania mushroom farmer. "Everybody's taking a hit with this."

At Ciarrocchi's farm, harvests have been reduced by 20 percent. Other farmers nearby have been hit far worse. Crop losses of up to 50 percent have been reported.

"This summer it has really gotten its fangs into farms and they are experiencing huge losses," said Dr. Paul J. Wuest, a professor at Pennsylvania State University's Department of Plant Pathology. "There are farmers closing their doors because of the green mold."

Green mold poses no threat to human health. When the light green fuzz develops in a farmer's compost, mushrooms simply don't grow. Scientists aren't even sure whether it attacks mushrooms or merely competes with them like unwelcome weeds.

Only an hour's drive from Baltimore, Pennsylvania's Chester County is the center and birthplace of the nation's mushroom industry.

Nearly half of the 789 million pounds of mushrooms produced annually in the United States comes from the state, and farmers in southern Chester County are by far the dominant producers.

Italian immigrants, many of whom labored in Philadelphia shipyards, came to this rural county to work in greenhouses. They introduced commercial mushroom growing to Quaker farmers exactly a century ago.

Today, their descendants own multimillion-dollar, climate-controlled, cinder block houses especially designed for

what has become a highly technical enterprise. Mushroom farmers monitor and manipulate oxygen, carbon dioxide, moisture, temperature and soil conditions to produce maximum yields.

"We are capital-intensive and labor-intensive business. It doesn't take much to throw things off," said Edward A. Leo, managing partner of John C. Leo & Son, a Chester County farm that grows 4 million pounds of mushrooms annually.

Green mold began to trouble Pennsylvania farmers three years ago. First reported in Ireland in the mid-1980s, the mold has reduced mushroom yields in Europe and Canada.

At first, U.S. farmers weren't overly concerned. Mushroom farmers can usually fight off invading mold, fungi and viruses that might like the damp, 60-degree environment of a mushroom house.

Farmers win most battles by playing close attention to farm hygiene -- pasteurizing compost, segregating crops, controlling insects, and making sure workers don't spread mold spores.

But the green mold has been a cunning opponent. The tactics have sometimes cut back on infestation. But then the mold bounces back worse than ever.

"The green mold is something we can't figure out how to control," said James A. Angelucci, general manager of Phillips Mushroom Farms in Kennett Square, where some crops have been reduced by 25 percent to 30 percent.

"I'm hearing from a lot more people who are affected this year."

At Ciarrocchi's "Sher-Rockee Farms," one full-time worker is assigned to hunt through mushroom beds stacked six decks tall for evidence of green mold. Like Romans destroying Carthage, workers must salt the decaying earth to thwart their foe. A mixture of rock salt and lime is dumped on top of the smallest outbreak. They don't dare dig the mold up for fear of spreading the tiny spore.

"It's a real battle, and it's been a battle for three years," said Ciarrocchi. "You get it. It drops off and then it spikes up higher. It's like the stock market."

Consumers have yet to feel the pinch from green mold. The wholesale price of about $1 per pound is the same farmers received in 1982, according to U.S. Department of Agriculture records.

In a sense, mushroom farmers may be victims of their own efficiency. A single square foot of mushroom bed produced nearly six pounds of white button, or Agaricus, mushrooms in 1995 -- twice what farmers could muster 20 years earlier.

The 1995-1996 crop, expected to be reported by the USDA on Aug. 16, may be just as abundant as the previous year's, with farmers from around the country filling the void, as have foreign producers.

Such competition has been a problem for small farmers. There are just 186 growers of white mushrooms nationwide compared with 514 as recently as 1985, said Laura L. Phelps, president of the American Mushroom Institute, the industry's trade group.

In recent years, more exotic varieties of mushrooms have helped some farmers expand their income. Portobello, shiitake, crimini, morel and enoki mushrooms have proven to be moneymakers, although they still represent a tiny fraction of the industry -- about 8 million pounds annually.

Baltimore Sun Articles
Please note the green-lined linked article text has been applied commercially without any involvement from our newsroom editors, reporters or any other editorial staff.