FLORENCE (AP) - A man who has been harvesting seaweed on the Oregon Coast for five years won't be allowed to continue. The state has refused to renew his permit.

James Jungwirth, an herbal product marketer from Williams, says seaweed has an array of health benefits, and its collection could become a cottage industry, providing much-needed jobs and income to Oregon's coastal communities.

When Jungwirth applied to have his seaweed harvest permit renewed, it prompted a discussion at the Oregon Department of Parks and Recreation about whether to allow commercial harvesting for him and other residents.

Some conservationists said there hasn't been enough research on the impact of seaweed harvesting on the rocky intertidal areas that are home to myriad species that thrive on sea plants.

“I'm disappointed,” Jungwirth said. “I'm hoping they're willing to go forward with the necessary research to look further into this.”

Seaweed is harvested commercially in 35 countries worldwide, bringing in an estimated $5 billion to $6 billion in sales for medicine, as gelling and thickening agents or in cosmetics and fertilizer, according to a report prepared by Laurel Hillmann, coastal resource planner.

There was a study attached to Jungwirth's experimental permit, but that's only the “first step” needed to understand what level of harvest the coast can sustain, Hillmann said.

“There is still no scientific information on the potential impact of commercial seaweed harvest on Oregon's nearshore ecosystems, and on the cumulative impacts of long-term harvest or multiple-harvester situations,” Hillmann said.

Though Jungwirth has been shut out of Oregon, he still has a permit to harvest seaweed in California.