Source: PENNSYLVANIA STATE UNIVERSITY submitted to NRP
USE OF SPENT MUSHROOM SUBSTRATE IN LANDSCAPE MULCH TO REDUCE THE ARTILLERY FUNGUS
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
HATCH
Reporting Frequency
Annual
Accession No.
0185530
Grant No.
(N/A)
Cumulative Award Amt.
(N/A)
Proposal No.
(N/A)
Multistate No.
(N/A)
Project Start Date
Jul 1, 2000
Project End Date
Dec 31, 2004
Grant Year
(N/A)
Program Code
[(N/A)]- (N/A)
Recipient Organization
PENNSYLVANIA STATE UNIVERSITY
208 MUELLER LABORATORY
UNIVERSITY PARK,PA 16802
Performing Department
PLANT PATHOLOGY
Non Technical Summary
In this study, we plan to determine an SMS/mulch blend can effectively contro the artillery fungus. If the blend is acceptable to the landscape industry and homeowners, this product could result in a reduction of the stockpiling of the compost. In addition, sales of the SMS to the landscape industry could result in a marketable product for the mushroom industry. Thus, results of this project may help to solve a disposal problem,, and open markets for use of the SMS as a salable product.
Animal Health Component
90%
Research Effort Categories
Basic
10%
Applied
90%
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
2044020110250%
2040650110250%
Knowledge Area
204 - Plant Product Quality and Utility (Preharvest);

Subject Of Investigation
0650 - Wood and wood products; 4020 - Fungi;

Field Of Science
1102 - Mycology;
Goals / Objectives
Disposal of spent mushroom substrate (SMS) is one of themajor problems facing themushroom industry in Pennsylvania, an industry that generates more that $560 million in farm gate receipts each. In Pennsylvania alone, nearly 700,000 cubic yards of SMS is produced annually. Although there is a limited market for an extremely small amount of the SMS, much of it is viewed as an undesirably byproduct within the mushroom industry and must be stored, and then disposed of properly. In recent years there has been a concurrent problem in the landscape mulch industry of Pennsylvania--a tremendous increase in home-owner complaints about tar-like deposits of the artillery fungus on the sides of their houses. We think that the increased problem is related to recent changes in mulch composition. These black spots are difficult to remove without damaging the surface of the siding or leaving a stain. The homeowner often places the blame and financial burden of responsibility back upon the landscape mulch manufacturer, supplier, or landscape contractor applying the mulch. The artillery fungus problem is currently one of the major pest problems facing the landscape mulch industry, which produces more than 2,000,000 cubic yards of mulch annually in Pennsylvania. Our objective is to determine if addition of SMS to landscape mulch will alter the mulch in such a way that it will not support the artillery fungus. Our preliminary research indicates that this is a very promising solution to two major problems. If successful, the incorporation of SMS into landscape mulch would have beneficial consequences for citizens and businesses in Pennsylvania. We think that it is possible to market a mulch blend containing 30% or greater SMS. This would utilize a significant amount of the SMS that must be disposed of each year in Pennsylvania. It would help to solve a disposal problem, as well as establish markets using SMS as a salable product to the landscape industry. Landscape mulches blended with other organic materials are already commercially available. In fact, the National Bark and Soil Producers Association has published guidelines for such mulch blends. Therefore, blending existing mulches with SMS, or creating new mulches based on SMS, should not present a marketing problem.
Project Methods
Mulches will be composted with different percentages of SMS. The resulting products will be incorporated in mulch dishes and in field plots. Since the vast majority of the mulch produced in Pennsylvania is derived from hardwood trees (e.g. oak and yellow-poplar), SMS will be incorporated only into the most popular, commercially available blends that are currently on the market. Experimental design: In both the laboratory studies and the outdoor field studies, a completely randomized design will be utilized. At least five of the most commonly used landscape mulches will be selected. SMS will be incorporated into each mulch at 0%, 5%, 10%, and 20% by volume. This will result in 20 treatments (5 mulches x 4 percentages of SMS); each will be assigned random positions in the laboratory and field plots. Each treatment will be replicated 3 times. Laboratory studies: Each of the 5 mulch treatments will be contained in covered glass dishes and kept moist. Each treatment will be inoculated with at least ten gleba of S. stellatus, collected from the lid covering a stock culture. Gleba will be spaced equidistant on the mulch 1 cm from the jar wall. Each treatment will be incubated at room temperature on lab benches in Buckhout Lab, and/or in a controlled-temperature growth room within the Department of Horticulture. Following initiation of sporulation, each glass lid will be examined weekly and the number of discharged gleba counted. The entire study will be replicated three times. Data (number of discharged gleba per unit area) collected from each of the treatments will be subjected to an Analysis of Variance using Minitab's GLM procedure. Interactions and main effects will be investigated; appropriate mean separation tests will be conducted as needed. Outdoor Studies: The same basic design as used in the laboratory will be used in the outdoor plots, but may be modified somewhat depending upon the initial results of the indoor tests. Three replications of 25 1-m square microplots have been established at the Penn State agricultural research farm. Each plot has one wall with a white, reflective surface. Treatments will be as described above, but the amount of inoculum will be increased appropriately. Targets will be examined weekly, beginning one month after inoculation, from the spring months through the fall months. The entire study will be repeated for at least 3 years.

Progress 07/01/00 to 12/31/04

Outputs
We evaluated 27 different mulches in the field to determine their ability to support growth and sporulation of the artillery fungus. Each mulch type was inoculated in 1998 with the artillery fungus and the amount of sporulation (number of spore masses on targets) determined annually until 2002, approximately 4 years after inoculation. We grouped the 27 mulches into nine general categories that had common characteristics: mulches that originated from large piles of bark and wood mixtures, mulches blended with 5% compost, cedar mulch, mulches commercially designated as "bark" but containing considerable wood, dyed wood chips, non-dyed wood chips, cypress mulch, large bark nuggets, and 100% spent mushroom substrate. The mulches obtained from large piles shredded blends of bark and wood supported significantly greater levels of artillery fungus sporulation than did other mulches. Such highly susceptible mulches should be avoided if the artillery fungus is to be minimized. In contrast, large bark nuggets, cypress mulch, and 100% spent mushroom substrate supported less artillery fungus. Other mulches supported intermediate levels of sporulation. All wood/bark landscape mulches will eventually support the artillery fungus over extended time periods (i.e., 3-4 years), and even more tolerant mulches should be replaced or covered with a fresh layer of mulch on a regular basis.

Impacts
During the last decade, the "artillery fungus" has emerged from an interesting mycological curiosity that grows in landscape mulch to a problem of major financial concern to homeowners, insurance companies, mulch producers, and landscape contractors. This common inhabitant of landscape mulch produces sticky spore masses (gleba) that it shoots towards the light or towards reflective objects such as light-colored automobiles or house siding. If the composted SMS/mulch blend effectively controls the artillery fungus, and the blend is acceptable to the landscape industry and homeowners, this product could result in a reduction of the stockpiling of the spent substrate. In addition, sales of the SMS to the landscape industry could result in a marketable product for the mushroom industry. Thus, results of this project may help to solve a disposal problem, and open markets for use of the SMS as a salable product.

Publications

  • Davis, D.D., Kuhns, L.J., Akina, K. and Harpster, T.L. 2004. Sporulation by the artillery fungus on 27 different mulches--a field study. J. Environ. Hort. 22:117-123.


Progress 01/01/03 to 12/31/03

Outputs
We are attempting to determine which landscape mulches, including blends made with spent mushroom substrate (SMS), favor or inhibit the artillery fungus. Field plots were established in 2001, and inoculated with the artillery fungus in 2002. The artillery fungus in the field trials began to sporulate in 2003. Preliminary data indicate that the 100% SMS mulch supports very little artillery fungus sporulation. Blends of various percentages of SMS with other mulches supported more sporulation. We have collected more than 100 S. stellatus isolates from various locations in the world (Japan, Europe, Alaska, Puerto Rico, etc.) to make geographic comparisons of rDNA using 4 different genes. We have discovered that S. iowensis, the other species in this genus, is much more common than previously thought. In addition, we have discovered at least one new species of Sphaerobolus.

Impacts
If the composted SMS/mulch blend effectively controls the artillery fungus, and the blend is acceptable to the landscape industry and homeowners, this product could result in a reduction of the stockpiling of the spent substrate. In addition, sales of the SMS to the landscape industry could result in a marketable product for the mushroom industry. Thus, results of this project may help to solve a disposal problem, and open markets for use of the SMS as a salable product. Knowledge of the geographic variation in the rDNA of the fungus may help explain why the problem is more severe in some areas than in others, and further our knowledge regarding molecular taxonomy of fungi.

Publications

  • Kuhns, L.J., Davis, D.D. and Brantley, E. 2002. 'Mulch' ado about nothing. Grounds Main. March: 24, 28, 30, 32.


Progress 01/01/02 to 12/31/02

Outputs
The overall objectives of this project are to determine which landscape mulches, including blends made with spent mushroom substrate (SMS), favor or inhibit the artillery fungus. Three years of sporulation data have been collected and analyzed from outdoor field plots, and a manuscript has been written for submission to a journal. A new set of field plots was established in 2001, and inoculated with the artillery fungus in 2002. The artillery fungus in the new field trials, as well as in new greenhouse trials, has yet to sporulate. In addition, we have collected Sphaerobolus stellatus isolates from around the world (Japan, Europe, Alaska, Puerto Rico, etc.) to make geographic comparisons of their genetic make-up and ability to sporulate. Genetic comparisons will also be made with S. iowensis, the other species in this genus, as well with as closely related genera.

Impacts
If the composted SMS/mulch blend effectively controls the artillery fungus, and the blend is acceptable to the landscape industry and homeowners, this product could result in a reduction of the stockpiling of the spent substrate. In addition, sales of the SMS to the landscape industry could result in a marketable product for the mushroom industry. Thus, results of this project may help to solve a disposal problem, and open markets for use of the SMS as a salable product. Knowledge of the geographic variation the DNA of the fungus may help explain why the problem is more severe in some areas than in others, and further our knowledge regarding molecular taxonomy of fungi.

Publications

  • No publications reported this period


Progress 01/01/01 to 12/31/01

Outputs
The overall objectives of this project are to determine which landscape mulches, including blends made with spent mushroom substrate (SMS), favor or inhibit the artillery fungus. We are also investigating potential bio-controls for control of the artillery fungus, and have just begun to collect S. stellatus isolates from around the world to make geographic comparisons of their genetic make-up and their ability to sporulate. One greenhouse experiment was established in fall 2001, and another is to be established in February 2002. Three years of data have been collected from outdoor field plots, and a new set of field plots was established in fall of 2001. One more year's data are needed from the older field experiment. The new field trial is to be inoculated in spring 2002, and the inoculated greenhouse trials are yet to sporulate.

Impacts
If the composted SMS/mulch blend effectively controls the artillery fungus, and the blend is acceptable to the landscape industry and homeowners, this product could result in a reduction of the stockpiling of the spent substrate. In addition, sales of the SMS to the landscape industry could result in a marketable product for the mushroom industry. Thus, results of this project may help to solve a disposal problem, and open markets for use of the SMS as a salable product. Knowledge of the geographic variation the DNA of the fungus may help explain why the problem is more severe in some areas than in others.

Publications

  • Brantley, E. A., Davis, D. D. and Kuhns, L. J. 2001. Biological control of the artillery fungus, Sphaerobolus stellatus, with Trichoderma harzianum and Bacillus subtilis. J. Environ. Hort. 19:21-23.
  • Brantley, E. A., Davis, D. D. and Kuhns, L. J. 2001. Influence of mulch characteristics on growth and sporulation of the artillery fungus Sphaerobolus stellatus. J. Environ. Hort. 19:89-95.


Progress 01/01/00 to 12/31/00

Outputs
The objectives of this project are to determine if mixing spent mushroom substrate (SMS) with landscape mulch will inhibit the artillery fungus, to investigate potential bio-controls present in SMS for control of the artillery fungus, and to determine if there are commonly-used landscape mulches on which the artillery fungus does not grow or sporulate. We are conducting four levels of experiments, from the molecular level to the field. These experiments involve: 1) molecular determination of the DNA fingerprint of S. stellatus, 2) mulch-agar petri plates in the lab, 3) mulch-dishes in growth rooms, and 4) mulch in outdoor field plots. These first three experiments have been completed. Results from the first two experiments have been submitted to a journal for publication. Data from the third experiment are being analyzed. The fourth (field) study is in progress, and will be complemented by a greenhouse experiment beginning in February 2001.

Impacts
If the composted SMS/mulch blend effectively controls the artillery fungus, and the blend is acceptable to the landscape industry and homeowners, this product could result in a reduction of the stockpiling of the spent substrate. In addition, sales of the SMS to the landscape industry could result in a marketable product for the mushroom industry. Thus, results of this project may help to solve a disposal problem, and open markets for use of the SMS as a salable product.

Publications

  • No publications reported this period