WOOD DECAY FUNGI AND FOREST RESTORATION

• Sponsoring Institution: Forest Service/USDA
• Project Status: ACTIVE
• Funding Source: USDA INHOUSE
• Reporting Frequency: Annual
• Accession No.: 0197024
• Project Start Date: Mar 26, 2002
• Project End Date: Sep 30, 2008
• Program Code: [(N/A)]- (N/A)

Recipient Organization
FOREST PRODUCTS LABORATORY
ONE GIFFORD PINCHOT DRIVE
MADISON,WI 53726

Performing Department
(N/A)

Non Technical Summary
The degradation of slash is an important source of nutrients and organic material for nutrient-poor forest soils of the American west and the Tropics. Mechanism to understand and accelerate slash degradation and decrease fire hazard using wood decay fungi will be investigated. Fire is currently the greatest danger to U.S. forests and much effort is going into thinning western forests to reduce fire hazard. The increased fire hazard due to beetle-killed trees in Alaska and other parts of the U.S. is significant. The rate of deterioration of beetle-killed trees by wood decay fungi is an important aspect of stand management, and techniques for rapid identification of decay fungi from logs and slash are being developed.

Animal Health Component

60%

Research Effort Categories

Basic

40%

Applied

60%

Developmental

0%

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
212	0612	1102	50%
212	0640	1102	50%

Knowledge Area
212 - Pathogens and Nematodes Affecting Plants;

Subject Of Investigation
0612 - Conifer forests of the West; 0640 - Tropical forests;

Field Of Science
1102 - Mycology;

Keywords

brown-rot fungi

fire

slash degradation

wood-decay fungi

Goals / Objectives
Wood-decay fungi play an important role in a 'healthy' ecosystem. They are responsible for recycling nutrients into the forest soil, often through the production of coarse woody debris by the activity of brown-rot fungi in temperate forests. The danger of fire hazard from slash and the large number of small diameter trees in the western forests is driving forest management to do heavy thinning that leaves a minimal amount of material on the forest floor. Wood-decay fungi can be used to accelerate decay of slash so that nutrients and organic matter can be returned to the soil while decreasing the fire hazard from the woody debris. The monitoring of decay fungi can also be used as a means of assessing different management techniques for their ability to recycle nutrients and prevent fire hazard. Wood-decay fungi can also bring value-added properties to woody debris whether generated from thinning of western forests or from the forest products industry, through the production of edible and medicinal mushrooms. Nutrient cycling in tropical forests, dominated by white-rot fungi, needs to be studied and the influence of decay fungi in forest restoration after major disturbances, such as tropical storms and hurricanes, is needed. Research is needed on the role of decay fungi in decreasing fire hazard.

Project Methods
Devastating fires in recent years have demonstrated the need for forest management techniques that decrease stand density of western forests, usually through processes of mechanical thinning. Research conducted by the FPL is finding ways to make use of this thinned material to provide an economic incentive for its removal. Some material should be left on the ground, however, to return nutrients and organic matter to the thin forest soils, primarily by generation of source wood debris by brown-rot fungi. This woody debris is a natural repository of mycorrhizal fungi that are necessary for seeding establishment. It is common to see new trees growing upon the remnants of ancient nurse trees. In 1981, it was recommended that 10-15 tons of debris be left behind during forestry operations to restore soil nutrients and organic matter, through generation of coarse woody debris by brown-rot fungi. Today, the recommendation is 2 tons due to the extreme fire hazard caused by slash and other forest debris. In the past, slash pine and other woody debris from forestry practices were burned. Concerns about forest fire and air pollution is stopping this practice. Wood-decay fungi, which can break down the complex polymers of wood, should be able to facilitate degradation of this material. Slash degradation by decay fungi has been researched for the past 50 years. Natural decay processes are slowed by waterlogging and freezing of the material in contact with the soil or by the rapid drying of wood and twigs not in soil contact. Dry material is at the highest hazard for fire. Previous studies have shown that specific fungal species are associated with different areas of the slash pile. Fungi that are resistance to high temperature and dry conditions of conifer slash inhabit the outer portions of the pile, those not in contact with the soil. Inoculation of slash piles with selected, local strains of these fungi could increase decomposition of the dry material, thus decreasing the fire hazard and increasing the release of nutrients to the soil. Accelerated creation of coarse wood debris by inoculation of logs with aggressive saprophytes would also be effective at returning organic material to the soil while reducing fire hazard. Some species produce edible and medicinal mushrooms; inoculation of these species would increase production of special forest products and help rural communities. Monitoring development of wood-decay fungi would give silviculturalists a way to assess the effectiveness of different thinning regimes on slash degradation and regeneration of organic material in forest soils. White rotters are the predominant decay fungi and the region is frequently swept by catastrophic windstorms and hurricanes. Research on the effects of decomposing wood on soil organic matter, fertility, and forest productivity is needed. New research will be initiated on the effects of white- versus brown-rot fungi in the develoment of organic matter in tropical soils. Mycological support for the analysis of wood-decay fungi will be provided to other researchers involved with global carbon cycle analyses.

Progress 03/26/02 to 09/30/08

Outputs
OUTPUTS: A book chapter was written that summarized fungal responses to disturbance including fire. Data on decay fungi associated with beetle-killed Lutz spruce in Alaska, which present a severe fire hazard, were further analyzed in anticipation of publication in 2009. This project is completed upon transfer of the work unit to the Northern Research Station.

Impacts
Anticipation of application of research by Alaskan forest managers after publication of project results in 2009.

Publications

• Miller, R. Michael; Lodge, D. Jean. 2007. Fungal responses to disturbance. Agriculture and Forestry. In: Kubicek, C.; Druzhinina, I.S., eds. The Mycota, 2nd ed., vol. IV, Environmental and microbial relationships. Berlin: Springer-Verlag: 44-67.

Progress 10/01/06 to 09/30/07

Outputs
Data were collated and statistically analyzed from the spruce rot decay study in Alaska. Publication is planned for 2008. A Senior Research Thesis was written by a student in the University of Wisconsin-Madison Department of Botany in which an experimental plan was developed to study the effect of using wood chips predigested by decay fungi to regenerate logging roads and to restore burned areas.

Impacts
Anticipation of application of research by forest managers after publication of project results in 2008.

Publications

• Vogelzang, Andrew. 2007. Controlling erosion on logging roads using myceliated and non-myceliated wood chips. Department of Botany, University of Wisconsin-Madison. Madison, WI: 13p. Senior Research Thesis.

Progress 10/01/05 to 09/30/06

Outputs
The development of DNA sequencing techniques for the rapid identification of wood decay fungi directly from logs and slash has been needed for ecological assessments of fungal decomposition in areas of high fire hazard, such as beetle-killed sites in southeastern Alaska. CFMR personnel have developed fast, low-cost techniques to isolate and amplify fungal DNA directly from wood samples using cloning techniques. Cultures obtained from beetle-killed Lutz spruce (Picea X lutzii) from snags and logs in the Dry Gulch stand of the Chugach National Forest were isolated using four different culture media. Species identifications were made by sequencing the ITS region of the rDNA and comparing to sequences from known databases. Fruiting bodies were also collected at time of sampling, dried, and identified using traditional morphological characteristics. A total of 1147 cultures were ultimately isolated from eight logs and three snags; 529 were identified by DNA sequencing of the ITS region. None of the selective media were effective at preferentially isolating the wood-decay Basidiomycetes. Many fungi were cultured that did not form fruiting bodies. Some fruiting bodies species were not isolated in culture. The fewest unique taxa were isolated from the dry Decay Class 2 snags, but they included important decay species. The greatest number of taxa was obtained from Decay Class 2 logs. The species accumulation curve shows that more sampling would result in even more taxa. Many Ascomycetes, including mitosporic forms, were cultured from all decay classes. Zygomycetes were prevalent in Decay Class 4 material. This study was presented at the Mycological Society of America meeting and will be published in 2007.

Impacts
Fire is currently the greatest danger to U.S. forests and much effort is going into thinning western forests to reduce fire hazard. The increased fire hazard due to beetle-killed trees in Alaska and other parts of the U.S. is significant. The rate of deterioration of beetle-killed trees by wood decay fungi is an important aspect of stand management, and techniques for rapid identification of decay fungi from logs and slash are being developed.

Publications

• Glaeser, J.A.; Lindner, D.L.; Banik, M.T.; Trummer, L. 2006. Wood decay fungi associated with beetle-killed lutz spruce from the Kenai Peninsula, AK. III. Culture data [Abstract]. Inoculum 57: 19.
• Lindner, D.L.; Allmer, J.; Banik, M.; Glaeser, J.; Stenlid, J.; Trummer, L.; Vasiliauskas, V. 2006. Community analysis of wood-inhabiting fungi using fruiting bodies, culturing, and rDNA [Abstract]. Proceedings of the 8th international mycological congress; 2006 August 21-25; Cairns, Australia. Congress Handbook and Abstracts Book 1. p. 147.

Progress 10/01/04 to 09/30/05

Outputs
The development of DNA sequencing techniques for the rapid identification of wood decay fungi directly from logs and slash has been needed for ecological assessments of fungal decomposition in areas of high fire hazard, such as beetle-killed sites in southeastern Alaska. CFMR personnel have developed fast, low-cost techniques to isolate and amplify fungal DNA directly from wood samples using cloning techniques. These procedures are currently being used to identify wood decay fungi associated with beetle-killed versus wind-thrown spruce from the Kenai Peninsula in Alaska. Data from DNA sequencing are being compared to identifications of fruiting bodies and fungal cultures. Spatial patterns of decay and physical properties of the degrading wood are also being assessed to provide an estimate on the amount of degradation of beetle-killed logs. Preliminary data suggest that bark beetle-killed trees decay faster than wind-thrown trees. Decay progresses from the base of the tree toward the top in beetle-killed trees, while decay proceeds from the top of the tree toward the base in wind-thrown trees. The brown-rot fungus Fomitopsis pinicola occurs more commonly in the base of beetle-killed trees. Wind-thrown trees have less fungal colonization at the base. Fifty-eight taxa were detected in a wind-thrown log, while 79 taxa were detected in a comparable beetle-killed log. Only 3 fruiting body species were observed on each log. DNA sequencing directly from the logs detected many more species per log than either culturing on artificial media or collecting fruiting bodies. Many fungi other than Basidiomycete decay fungi were detected using sequencing. Taxa accumulation curves based on sequence data indicate that sampling is still incomplete, and that more sampling would detect even more fungal species per log.

Impacts
Fire is currently the greatest danger to U.S. forests and much effort is going into thinning western forests to reduce fire hazard. The increased fire hazard due to beetle-killed trees in Alaska and other parts of the U.S. is significant. The rate of deterioration of beetle-killed trees by wood decay fungi is an important aspect of stand management, and techniques for rapid identification of decay fungi from logs and slash are being developed.

Publications

• Lindner Czederpiltz, Daniel L.; Banik, Mark T.; Micales, Jessie A.; Trummer, L. 2005. The effect of mortality agent on fungal succession and decay rate in Lutz spruce [Abstract]. Inoculum 56(4): 36.

Progress 10/01/03 to 09/29/04

Outputs
The development of DNA sequencing techniques for the rapid identification of wood decay fungi directly from logs and slash has been needed for ecological assessments of fungal decomposition in areas of high fire hazard, such as beetle-killed sites in southeastern Alaska. CFMR personnel have developed fast, low-cost techniques to isolate and amplify fungal DNA directly from wood samples using cloning techniques. This procedure was tested on the identification of fungal species from spruce logs collected in Sweden. The number of clones that need to be sequenced from each sample and the number of samples needed per log for statistical analyses were determined. A total of 1,476 clones have been sequenced from the Swedish logs, and the data on community composition are being analyzed. These procedures are currently being used to identify wood decay fungi associated with beetle-killed versus wind-thrown spruce from the Kenai Peninsula in Alaska. Data from DNA sequencing are being compared to identifications of fruiting bodies and fungal cultures; preliminary data show that the sequencing procedures detect many more fungal species per log than traditional collecting and culturing techniques. Spatial patterns of decay and physical properties of the degrading wood are also being assessed to provide an estimate on the amount of degradation of beetle-killed logs.

Impacts
Fire is currently the greatest danger to U.S. forests and much effort is going into thinning western forests to reduce fire hazard. The increased fire hazard due to beetle-killed trees in Alaska and other parts of the U.S. is significant. The rate of deterioration of beetle-killed trees by wood-decay fungi is an important aspects of stand management, and techniques for rapid identification of decay fungi from logs and slash are being developed.

Publications

• Croan, Suki C. 2004. Conversion of conifer wastes into edible and medicinal mushrooms. Forest Products Journal 54(2): 68-76.
• Czederpiltz, Daniel L.L.; Stenlid, Jan. 2004. Determining fungal succession in Picea abies logs using direct analysis of community rDNA sequences, culturing, and fruiting bodies [Abstract]. Inoculum: Newsletter of the Mycological Society of America 55(4):12.
• Micales-Glaeser, J.A.; Banik, M.T.; Haight, J.; Trummer, L. 2004. Wood decay fungi of Lutz spruce from the Kenai Peninsula, AK [Abstract]. Inoculum: Newsletter of the Mycological Society of America 55(4): 27.

Progress 10/01/02 to 09/30/03

Outputs
The study on growing edible and medicinal mushrooms from conifer slash and waste from the forest products industry was finished upon retirement of the principal investigator. It was concluded that edible and medicinal mushrooms could be grown on conifer wood if it is pretreated with sapstain fungi that remove the resins from the wood. A position was approved for hiring a new scientist who will work in this problem area beginning in FY 2004.

Impacts
Fire is currently the greatest danger to U.S. forests and much effort is going into thinning western forests to reduce fire hazard. It is important to leave some material on the forest floor so that decay fungi can recycle nutrients from the wood back into the soil. Thinning techniques that reduce fire hazard and accelerate decay are being investigated.

Publications

• Croan, Suki C. 2003. Utilization of treated conifer wood chips by Pleurotus (Fr.) P.Karst. species for cultivating mushrooms. Mushrooms International. The Official Newsletter of the International Society for Mushroom Science 91: 4-7.
• Croan, Suki C. 2003. Bioconversion of conifer wood chips into specialty mushroom producing fungal growth. Mushrooms International. The Official Newsletter of the International Society for Mushroom Science 90: 7-11.

Progress 10/01/01 to 09/30/02

Outputs
A study was completed on the use of sapstain fungi to stimulate the colonization of conifer waste wood (slash and sawdust) by edible, wood-inhabiting fungi. It was determined that pretreatment with an albino strain of a bluestain fungus that is used commercially to remove resins from chips in the papermaking process was able to degrade extractives that normally inhibited colonization of conifer waste by species of Pleurotus and the shiitake mushroom, Lentinula edodes. This information was presented at the International Conference on Mushroom Biology and Mushroom Products in Mexico. DNA sequencing analysis was used to identify cultures of decay fungi isolated from slash collecting in field plots in northern Idaho in which different thinning treatments were used to determine how best to leave some slash in the forest for soil nutrient replenishment through decay. Results from sequencing were compared to identifications made from fruiting bodies growing on the material. Different species were identified using the two different techniques. These data will be used as a baseline to compare future collections that will be made as the slash decays further. A DNA sequencing library of ITS regions of the major brown-rot decay fungi in the western U.S. was established in order to aid with future identifications.

Impacts
Fire is currently the greatest danger to U.S. forests, and much effort is going into thinning eastern forests to reduce fire hazard. It is important to leave some material on the forest floor so that decay fungi can recycle nutrients from the wood back into the soil. Thinning techniques that reduce fire hazard and accelerate decay are being investigated.

Publications

• Micales, J.A.; Banik, M.T.; Norton, K.; Graham, R. 2002. Brown rot fungi associated with thinning treatments in northern Idaho. Inoculum 53(3):44-45.