4/20/2013 7:00 AM
By Laura Zoeller Southwestern Pa. Correspondent
GIBSONIA, Pa. — Growing shiitake mushrooms can be more than just a hobby. It can also be incorporated into a forest management program as a money-making diversification for farmers.
Allen Matthews, director and instructor of sustainable agriculture at Chatham University, spoke about shiitakes during a Pennsylvania Association for Sustainable Agriculture workshop recently at the University’s Eden Hall Campus.
“Shiitake mushrooms are low in calories, a good source of protein and fiber, can be high in vitamin D, and are thought to be medicinally valuable,” Matthews said.
“Current studies show that they can aid in the buildup of a healthy immune system as well as help reduce stress,” he said. “Plus, log-grown shiitakes are more flavorful and delicious than their commercially grown counterparts.”
The grower would begin by cutting bolts, or logs, for the mushroom spawn to be put into, choosing logs that are less than perfect.
“Keeping in mind that the tree needs to be living when you start, which trees would you cut down if you were preparing to thin out your wood lot?” Matthews asked. “Ones with burls, knots, low forks, woodpecker marks, dead limbs and other imperfections would be among the first to go. Many of those would be perfect for mushrooms.
“While our research has shown that white oak, red oak, American beech, sugar maple, hornbeam and hophornbeam provide the most consistent results, some growers have had success in other varieties, such as ash,” he said.
A bolt is usually about a yard long, and should be no more than 8 inches in diameter because it will have to be moved around several times over the course of a year or two.
“It should be cut in February or March, when the sap is coming into the tree, but before it has begun to bud out, so that the bolt has its highest possible moisture content,” Matthews said. “Then, it should be left to rest for a week or two after felling to allow other funguses time to die off before inoculating it with mycelium, the shiitake spawn.”
The inoculation process begins when the log has a series of holes drilled into it and is completed when the spawn has been packed into the holes and sealed with cheese wax.
“We used an angle grinder with a 3/16th inch bit,” Matthews said, “because the tip of our inoculator is 3/16th of an inch.”
Holes are drilled about four inches apart in rows a few inches apart all around the log. After the spawn is packed into the holes and sealed with wax, the log will need to be stacked on a pallet in a shady area and kept cool and moist for an entire year.
“Next spring, we will shock’ these logs by soaking them in water for about 24 hours,” Matthews said. “Then we will lean them upright, like an A-frame, for a week or two until they begin to bloom.”
Though a crop wouldn’t be seen for a year, growing shiitake mushrooms could be a profitable endeavor.
“If you inoculated 100 logs in the first year, it would cost you about $362 in equipment,” Matthews said. “It would be a bit less than that if you already own a chainsaw.
“You would receive no payback that first year,” he said. “But considering that shiitakes sell for around $8 per pound for wholesale and $16 per pound for retail, and if you consider that one log can produce two pounds of mushrooms per year, if you prepared 100 logs per year for four years, you could gross $12,000 per year by year four.”
Variables to those numbers include the size of the bolt, the wood pH, the density of the log and moisture.
“One of the most important factors is moisture,” Matthews said. “Keep that in mind when selecting the site where you will rest your bolts for a year. You can manufacture shade around them relatively easy, but it is not so easy to take 100 logs to water if you need to rewet them. Make sure water is accessible at your site.”
Research about the economics of a shiitake mushroom enterprise, as well as best management practices, can be found at www.sare.org by typing “shiitake” into the search bar.
“It can help you determine whether shiitake mushroom cultivating might be a good fit,” Matthews said. “But don’t discount its merits as an enjoyable hobby if you decide it isn’t an income source for you. Cut some logs, and then call some friends. Have an inoculation party, and next year, enjoy the harvest.”