Off-label fungicide use is sought to protect Hawaii coffee farms

A battle over the health of Hawaii coffee farming is intensifying with state officials seeking federal approval for off-label use of a fungicide to combat a pathogen threatening more and more of the industry.

The state Department of Agriculture filed a request Wednesday with the U.S. Environmental Protection Agency to let local coffee farms fight a leaf fungus with a fungicide that the EPA allows as a treatment on many crops — including strawberries, tomatoes, potatoes, sugar cane, soybeans and wheat — but not coffee.

HDOA’s request to use Priaxor Xemium, made by BASF, follows Gov. David Ige declaring an emergency for Hawaii’s coffee industry last month following a move in November by the state Board of Agriculture determining that Maui and Hawaii island were infested with coffee leaf rust and restricting movement of coffee plants, plant parts and certain materials on those islands.

The Board of Agriculture has tentatively scheduled a meeting for Tuesday to consider expanding the same designation and quarantine to Oahu and Lanai after more recent detection of the fungus on these islands.

“Coffee leaf rust is a plant pathogen that cannot be eradicated once it takes hold so it’s important that we use all available tools, including the use of fungicides, to help manage the problem,” Phyllis Shimabukuro-Geiser, board chairwoman and HDOA director, said in a statement.

Coffee has been a roughly $50 million industry in Hawaii in recent years, and the second-biggest crop in the state by value despite struggles with another plague, the coffee borer beetle.

According to the Hawaii Coffee Association, there are nearly 1,500 coffee growers statewide who are vulnerable to the fungus, which can wipe out whole farms in a matter of weeks because rust-resistant varieties are not grown here.

The fungus can cause severe plant defoliation that leads to stunted plant and coffee cherry growth.

“We’re facing the most destructive coffee disease in the world,” the association said in a February announcement online that said the fungus causes $3 billion in annual damage and lost income globally.

Coffee leaf rust, or Hemileia vastatrix, was first discovered in Sri Lanka in 1869 and ended up wiping out that island’s vast coffee production, which was eventually replaced with tea.

The pathogen today is found in coffee-growing regions in Southeast Asia, Africa and Central and South America.

Hawaii’s coffee industry and regulators have long tried to keep coffee leaf rust out of the state, in part by restricting imports of coffee plants and nonfumigated green coffee beans.

University of Hawaii scientists first detected the fungus locally in October on Maui.

HDOA said the EPA’s review could take up to 45 days. If the EPA approves the requested fungicide use, such use would be allowed for up to a year, or longer if the EPA adds coffee to the list of plants that can be treated with Priaxor Xemium.

Meanwhile, HDOA said other efforts to minimize impacts from coffee leaf rust are ongoing. These include importing disease-resistant plants, encouraging farmers to follow best management practices to reduce the risk of spreading coffee leaf rust, and urging farmers to look for the fungus, which the agency estimates can cause losses ranging from 30% to 80%.

“We ask all those who have coffee plants to survey their plants and report possible infections so various management strategies may be implemented to minimize the impact on our important coffee industry,” Shimabukuro-Geiser said.

Suspected infestations should be reported to HDOA’s Plant Pest Control Branch at 973-9525.