Soft fruit crops in Somerset County have been hit by a new pest that has worked its way into the region.
The spotted wing drosophila is a small vinegar fly that damages red raspberries, black raspberries, blueberries, cherries and strawberries. Maggots develop in the fruit.
"It is devastating," Tom Ford, Penn State Extension horticulture educator, said in a telephone interview. "One Amish farmer told me he lost 5,000 pounds of blackberries. He dumped them in a hole and burned them. Growers were blindsided. One told me that everybody on his road — and this is a road that is several miles long with multiple farms — had plantings decimated. It will continue to spread to the home gardens."
Many growers have stopped picking their fruit because of the infestation, he said. That is the wrong course of action.
"We want them to destroy the crop; otherwise if you let it sit in the fields, it becomes a nursery and will really wreak havoc next year," Ford said.
While fruit growers monitor for pests and spray on a regular basis, most people don't spray the small fruit heavily. The good news is that the spotted wing drosophila doesn't impact the health of the main plant.
Dr. David Biddinger, entomologist at the Penn State Fruit Research & Extension Center, said unlike other vinegar flies that target damaged or overripe fruit, drosophila females will attack any soft-skinned healthy fruit to lay its eggs. The flies cannot travel very far under their own power. Identification of the adult is difficult because of its small size. The adults thrive at cool temperatures. Females live up to nine weeks and can lay more than 300 eggs.
A disease that heavily damaged tomatoes in 2009 isn't as bad this year. The late blight is still in Somerset County, Ford said, but it isn't as aggressive this year.
"It hit potatoes early in June, then tomatoes," he said. "When it got hot and dry, the disease disappeared. We've received more reports about it since the rains in early August."
Some of the blight outbreaks were caused by infected seed potatoes. Some growers took their leftover potatoes and threw them on the fields, thinking cold weather would kill the blight. But it wasn't cold enough last winter to kill it.
"Some tomato growers are seeing the blossom end rot," Ford said. "Fruits blacken. It is a calcium deficiency, not a disease. It occurs when plants are under stress: too dry, too hot, too wet or too cool — any extreme weather condition."
There were some localized shortages of sweet corn this year, which has resulted in prices between $3 and $4 a dozen locally. In other parts of the state, sweet corn routinely costs between $5.50 and $6 a dozen. Ford said that corn may have more value because it is a superior product.
He is also warning people that the hemlock woolly adelgid is present in hemlocks in Somerset County. That is spread by birds. He recommends people who have hemlock stands remove any birdbaths or feeders. The hemlock woolly adelgid killed 90 percent of hemlock trees in Shenandoah National Park in Virginia.