Field study of technique for combining low-cost, herbicide-free control of woody invasives, in particular Ailanthus altissima, with production of edible mushrooms
April 2008: I identified 8 test plots (Plots A-H), containing 25 Ailanthus trees each. Marked test trees w/tree paint and took GPS coordinates. In communication with my ODNR service forester and collaborator, Cotton Randall, plots were selected with similar soil type, aspect, slope, and light exposure. Treatments were scheduled over the course of a typical winter forest management season (November - mid-April), broken down into the following 4 periods:
Period 1: Plots A & B treated Dec. 2008, inoculated Jan. 2009
Period 2: Plots C & D treated Jan. 2009, inoculated Feb. 2009
Period 3: Plots E & F treated Feb. 2009, inoculated Mar. 2009
Period 4: Plots G & H treated Mar. 2009, inoculated Apr. 2009
This is a slight modification of the original proposal, based on both adjustments necessitated by access to appropriate equipment and supplies (custom plug spawn requires a minimum of 5 weeks to produce) and on expert advice from mushroom professionals. For example, a lag of several weeks between treatment and inoculation allows time for the anti-fungal substances present in healthy trees to dissipate. This is typical for more conventional cut log mushroom inoculation.
Late October – early November 2008: Using grant funds, I attended Growing Gourmet and Medicinal Mushrooms seminar at Fungi Perfecti outside Olympia, WA, taught by Paul Stamets, one of the leading authorities on mycoculture in the U.S. During the course of seminar, I learned tissue culture techniques for mushroom propagation, most importantly how to produce my own plug and/or sawdust spawn.
November 2008: Purchased and assembled equipment, supplies, and reference materials for the project. Found a supplier for local Ohio strains of native culinary mushrooms and identified 3 target mushroom species suitable for growing on logs/stumps: Pleurotus ostreatus “Ohio White” (White Oyster), Pleurotus ostreatus “Ohio Brown” (Brown Oyster), and Laetiporus sulphureus (Chicken of the Woods). These strains, many supplies, and valuable advice were provided by Mushroom Harvest in Athens, OH.
December 2008: A labeling system containing unique tree identification number (T1-T200) and treatment identification code composed of the plot code plus a random number between 1 and 25 (A1-A25, B1-B25, C1-C25, etc.), to be attached to each tree, was developed. I was assisted in structuring these test plots and planning for future data analysis by Dr. Frank Hassebrock, Psychology, Denison University. Trees were sorted by size within each plot and then randomly assigned to one of the following five categories of treatment:
C = control; no treatment
B = baseline; treatment alone, no mushroom inoculation
M1 = treatment plus mushroom inoculation with Pleurotus ostreatus var “Ohio White”
M2 = treatment plus mushroom inoculation with Pleurotus ostreatus var “Ohio Brown”
M3 = treatment plus mushroom inoculation with Laetiporus sulphureus
Plots A and B, i.e., trees T1-T50, were measured, labeled and then treated for Ailanthus control. Data was collected for each tree including before and after photographs, moisture content readings from treated and untreated portions of the tree, and diameter reading at time of treatment. For the initial inoculations, I ordered fully incubated (ready to use) plug spawn and test tube cultures (slants) for the three strains of mushroom from Mushroom Harvest. The slants will be used to generate my own plug spawn.
January 2009: Plots A and B (trees T1-T25, T26-T50) were inoculated with the three strains of native mushroom spawn using plug spawn purchased from Mushroom Harvest. Weather was a decided factor in the inoculation process, requiring temperatures at least theoretically above freezing. Fellow farmer Andrew Semler was of particular assistance by bringing over his much more powerful cordless drill to help me inoculate trees when mine failed. Measured, labeled, and treated Plots C and D (trees T51-T75, T76-T100). Weather was less of an issue for Ailanthus treatment, only requiring the temperature to be above about 20°F. I also began the laboratory portion of the project to produce spawn from tissue culture slants, with technical assistance from my Chemistry faculty collaborators Dr. Dick Doyle and Dr. Peter Kuhlman as well as additional advice from Dr. Tony Layson. I grew out all three cultures to be used in the study, as well as others acquired at the Stamets seminar, on agar media in petri dishes.
February 2009: Photographed all the steps in the processes used to treat and inoculate the Ailanthus trees for use in future presentations and on the website. Presented a poster at the annual Ohio Ecological Food & Farm Association (OEFFA) conference in Granville, OH. A tentative date in late October 2009 for a landowner's workshop sponsored by the Licking Co. SWCD and Ohio DNR Division of Forestry and based on this research project was discussed in conjunction with collaborators ODNR forester Cotton Randall and SWCD District Manager Jim Kiracofe. Plots C and D were inoculated, Plots E and F (trees T101-T125, T126-T150) were measured, labeled, and treated. In the lab, I propagated the mushroom cultures from agar media (petri dishes) to sterilized grain media (qt. jars) to create grain masters. Expanded the grain masters into sterilized wooden dowel plug media (half-gallon and gallon jars) at a rate of approximately 4 to 1. Created duplicate test tube slants of cultures as library backups in case of contamination or other disaster.
Summary of project expenses to date:
Operating costs and supplies: $1741
Equipment, seeds, spawn, etc.: $334
NOTE: Because I've been able to move towards producing my own spawn, the cost burden has shifted from Equipment & Seeds, e.g., commercial spawn, into Supplies, e.g., agar media, rye grain, dowels, etc. for producing my own equivalent. Originally I was unsure whether I would be able to successfully produce my own spawn, so budgeted for all commercial spawn. It appears that I will be able to supply between ¼ and 1/3 of my own spawn for the project.
Because of the winter nature of my project, I am only half way through the proposed research. I have no results, per se, to discuss at this time. I do, however, have some lessons learned to share.
Time, labor, and equipment: Drilling trees in the winter requires either a more powerful drill than I expected, or a lot more time. Even when the ambient air temperature is above freezing, portions of the tree may still be frozen, e.g., the north-facing side. I ended up purchasing a new 36V cordless drill with 2 rechargeable batteries. My existing cordless drill was able to drill less than half a tree on a charge. While it is possible (and not physically more difficult) to drill the trees using a bit brace, the going is very slow, taking up to an hour to process a single tree, compared to drilling & inoculating 5 trees in 2 hours with the new drill. With 2 battery packs, I can inoculate 10 trees (5 per battery), go home for lunch and to recharge the batteries, then go back out and process another 10 trees in a single day. Processing so many trees at a time is sometimes necessary since, as mentioned above, finding an appropriate window of opportunity regarding weather can be difficult. The cost of the drill was not included in my original budget, but I anticipate being able to use it for numerous other projects on the farm.
A relatively inexpensive lumber & building materials moisture content meter (~$80) is extremely useful for gauging relative changes in moisture content in the trees. A general observation is that the areas of the tree with bark (the inoculated areas) have maintained a fairly steady moisture content while the treated areas below vary widely depending on the weather and recent rainfall.
A rule of thumb for cut log inoculations is that you don't want the moisture content of the wood substrate to drop much below 25% during the incubation period. Having the ability to compare moisture content readings throughout the next year will be very informative when determining the incubation success or failure of the mushroom spawn. This was not on my original supplies request, but I have found it invaluable so far.
The drill and 2 slim-pack batteries (together 6.5 lbs.), drawknife, hammer, moisture meter, camera, GPS, labels, nails, plug spawn for 3 different species (typically 3-5 lbs. ea), and notepad in a pack basket came to about 25 lbs. of equipment to be carried on foot on the trails. Hefty, but not impractical. Some of that equipment is only necessary for research; in production mode, I would expect the weight to drop by at least 5 or 10 lbs.
WORK PLAN FOR 2009
March 2009: Inoculate Plots E and F. Treat Plots G and H. Continue to expand mushroom spawn onto wooden dowel plugs for use in inoculations. Do two workshops/presentations on mushroom log inoculation, with mention of this SARE project research as pertinent. Work on website development.
April 2009: Inoculate Plots G and H. Initiate regular weekly inspection routine, with periodic data collection, e,g., moisture content readings. Work on website development.
May 2009 – mid-October 2009: Do weekly inspections of test plots, more if weather indicates likelihood of mushroom production, although it is unlikely that any fruiting will occur before fall at the earliest. Finish developing project website. Distribute flyers at farmers market and update website as appropriate.
Late October -early November 2009: Host a landowner's workshop, sponsored by Licking Co. SWCD and Ohio DNR Division of Forestry.
November - December 2009: Revisit, measure, and photodocument all trees in the study.
Continue regular inspections. Analyze accumulated data for effectiveness of the various mushroom and baseline treatments.
January - March 2010: Write up final report. Give talk at OEFFA conference and other venues, as available. Update the website as appropriate.
Several people have toured my research plots and/or assisted me with the measurement, labeling, treatment and inoculation of the plots, including neighbors, fellow farmers, Denison Biology faculty, Denison Chemistry faculty, and other interested forest landowners who were intrigued by my OEFFA poster presentation.
Others with an interest in this project have provided expert assistance to me in learning and improving my sterile laboratory techniques: Dr. Dick Doyle, Dr. Peter Kuhlman, and Dr. Tony
Dr. Frank Hassebrock, Psychology, Denison University made comments and suggestions on ways to improve the layout, timing, data collection, and labeling of my test plots to make later statistical analysis of data more meaningful and rigorous.
Poster presentation at the 2009 OEFFA conference: I spoke with probably a dozen people with explicit questions about my research.
I have scheduled two demonstrations/workshops on mushroom log inoculation for March 2009; I will include mention of my Ailanthus-mushroom research in my presentations and make the poster available for viewing. One presentation to the Licking Co. Herb Society will reach an audience of about 15 people. The other, a half-day hands-on workshop, will be attended by 5-6 people.
A number of people have expressed interest in my research and requested email copies of the research abstract. These include the owner of Mushroom Harvest (Athens, OH), George Vaughn, the co-owner of Field and Forest Products (Peshtigo, WI), Mary Ellen Kozak, and Fred Nickerson, CPA and fellow tree farmer (Granville, OH).
Other future outreach plans include the following:
• Development of a web resource describing the nature of the project and the results, due to go live by the end of May 2009.
• Flyer describing the project made available at my booth at the Granville Farmer's market, last weekend in May through mid-October.
• Landowner's Day sponsored by Licking Co. SWCD for late October or early November.
• An OEFFA Farm Tour in conjunction with the SWCD/Forestry landowner's day is also a possibility.
• Presentation/talk at annual OEFFA conference, February 2010.
• POWA (Promoting Ohio Women in Agriculture) workshop/program for March, June or September 2010.
• Ohio Mushroom Society foray, tentative for late 2010 when fall mushrooms are at their peak and the inoculated trees have had plenty of time to incubate.
• Homeschool presentation with the Roshons and others.