WINTHROP &#8212 An Independence man hopes his business can mushroom into a multi-million dollar enterprise.

Tim Miller grows shiitake mushrooms.

Miller started his business, Mid-American Bio-Ag, two years ago. He said he recently harvested more than 400 pounds of the East Asian delicacy. He is hoping to grow up to 75,000 pounds in the not-so-distant future.

He said he and his father grew the mushrooms 20 years ago using four-foot logs, but that process was difficult and time-consuming. Now, Miller says, he has sped up the process using sawdust blocks.

“It takes you two to three years to get mushrooms on a log,” Miller said. “With a sawdust technique, I can get them in 60 to 90 days.”

He grows them in two nondescript farm buildings south of town. Inside, the sawdust from a local lumber company is combined with other material to promote growth. It is then put in plastic bags and sterilized in an autoclave to remove harmful bacteria or poisonous fungi.

Miller also grows the reishi mushroom, which is used as a natural cancer treatment overseas.

While the shiitake mushrooms can sell for $6 a pound wholesale, the reishi mushrooms can sell for as much as $100 a pound in China and Germany.

Miller hopes to eventually harvest more than 100,000 pounds of shiitake mushrooms each year.

He also is seeking organic grower’s certification from the state of Iowa, which he said will boost the price of his product.