The fragrant process that brings fungi to the dinner table begins when Needham's crew salvages straw bedding from horse tracks and stables, mixes in fresh hay and manure, and spreads it out in long rows for seven to 14 days to naturally pasteurize it. As bacteria living in the manure break down its nutrients, their metabolism raises the temperature to more than 120 degrees F (50 degrees C), leaving only the hardiest organisms alive. Mushroom farmers call this the pasteurization because it also kills off many unwanted fungi, which could steal nutrients from the buttons. The manure stench itself isn't so bad, but after a few days, oxygen levels in the pile decline, encouraging growth of anaerobic bacteria, which do not require oxygen and emit gases reeking of rotten eggs. The problem, Royse says, is that sulfur "has got a real low odor threshold so you can smell it from far away." In addition, water runoff from compost piles pollutes groundwater and open streams.
In 2002 Royse's colleague Paul Heinemann found that installing air jets beneath compost piles in bunkers could keep foul odors down by encouraging the growth of the aerobic (oxygen-dependent) bacteria. He measured airborne sulfurs around the sites and enlisted experts trained by the Monell Chemical Senses Center to rate odors between "barely detectable" and "strongest imaginable". In other studies, Heinemann put Gore-Tex breathable fabric over compost piles to reduce smells, and he even got mushrooms to grow on grain rather than compost.
But Royse realized there might be a way to cut those mountains of compost down to molehills, which would have the benefit of reducing costs, along with odor and pollution problems. After the second flush of mushrooms, the yield from a third flush is so low it's hardly worthwhile; even so, at this point the mushroom crop has only consumed 20 percent of mass of the compost material. The rest is dumped. "That's a shame,” Royse says, "If we could add that 20 percent back and get another crop, that would be a lot more efficient."
The challenge is to figure out what nutrients the mushrooms have actually sucked out of the compost that lead to the 20 percent reduction in its mass. Then, Royse will have to find a practical method to prevent molds and other mushroom pathogens from infiltrating the soggy substrate during a second crop with two additional flushes.
In another room, Royse has divided up experimental compost mixtures into nine different treatments on which he will test the effect of adding supplements including isoleucine, which he reported in 2008 as the most important amino acid for stimulating mushroom yield of the second crop. Other amino acids like valine are also important, but his research has shown that isoleucine alone can increase second crop yield by 68.7 percent.
A couple of mushrooms have poked through the soil, and I ask Royse if that's the second crop. "We're trying to triple-crop," he says, "We're getting greedy."
His secret weapon is a piece of landscape cloth, which he places between the compost and the top layer of peat moss that growers call the casing. Once one crop is complete, Royse can toss out the peat moss, supplement the compost, and add a new layer of peat already infiltrated with fungus. The filaments of genetically similar fungi can reconnect through holes in the cloth. "They hook those pipes up and nutrients start to flow," he says. Royse and his team are also experimenting with another fungus, Scytalidium thermophilum, which helps mushrooms grow on unpasteurized compost and keeps competing organisms from colonizing the manure.
The problems don't end once the mushrooms have been harvested one, two or even three times. Disposing of that spent compost—which begins to reek again after harvest—is costly as well as an environmental liability. Recently, however, it has proved to be a remarkable natural agent against an insidious pest, says Penn's Donald Davis. The artillery fungus lives in bark mulch and has evolved to shoot its tiny spores at bright surfaces, like the sides of cars and homes. It may sound like nothing, but the spores are practically impossible to remove and after a series of lawsuits, homeowner's insurance companies now exclude the vermin from their policies. Davis found that adding 40 percent of the spent mushroom compost to mulch mixtures eliminates the pest.
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7 Comments
Add Commentif you don't like the smell of agriculture, stay in the city?
Reply | Report Abuse | Link to thiscities stink! I'll take the smell of agriculture in the country any day. if you don't like smell of manure don't buy a house down wind.
Reply | Report Abuse | Link to thisThis sulfur emitted by the compost business is toxic. We have had several environmental tests done in this area and they KNOW it's toxic, but the township has been fighting archaic agricultural laws to get these industrial farmers out. This is not your run-of-the-mill "farm". It's like having a toxic waste dump in your back yard. We were here BEFORE this new greatly increased polluting method of composting was introduced. We are trying to save our environment while the mushroom compost folks are systematically destroying it. We have encouraged composters to use new technology to cut out the odors, and some mushroom compost farmers have done so with great success. Needham refuses. He should not be allowed to endanger our kids whose school air lies in the path of the fumes he emits. Its noxious and unsafe, and our kids are out playing on a football field that reeks. Its unhealthy and has driven countless other businesses, as well as homeowners, out of town. Property values plummet and Needham gets rich. We are wasting tax dollars as Needham drags his feet forcing this never-ending court case to continue. How does he sleep at night??
Reply | Report Abuse | Link to thiswhy make them enviromentaly friendly? they are fungi and they tast desgusting anyway.
Reply | Report Abuse | Link to thiswhy make them enviromentaly friendly? they are fungi and they tast desgusting anyway.
Reply | Report Abuse | Link to this"farm odors are a national problem that are pitting agricultural economies against a deluge of suburbanites who thought they wanted a piece of the country lifestyle."
Reply | Report Abuse | Link to thisWhy is an aspect of prior use not entirely grandfathered in the zoning laws? People who move into the country should be made to be accepting of the fact they may see and smell cows.
Or they can stay in the city.
Why would you choose to live in an area where you know this is what you will live with? This farm has been there for generations, much longer than most of the houses nearby. If you want them to build the modern, odor reducing systems to compost, perhaps you should donate $20,000,000 plus or minus to help them get it done. I am sure in this economy it wont be a problem. People move out to the country and all they do is whine about the odors, the bugs, how far it is to the store, etc....
Reply | Report Abuse | Link to thisI recommend moving.