The Latest and Greatest: FPL's NewsLine Hits the Web!

FPL researchers are hard at work discovering the amazing possibilities wood presents to make our lives safer and better. You can read all about what they’ve been up to in our quarterly newsletter, NewsLine.

newsline-2015-2-thumbIn this issue, you’ll learn about the importance of fasteners in keeping your deck safe, research on wood bridges, a new demonstration house, recycling preservative-treated wood, the amazing things we can do in our new pressure treatment plant, and much more.

Past issues of NewsLine can be found on FPL’s website.

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We hope you enjoy this issue and wish you a wonderful holiday season.

-The Newsline Team

Timber Turn-Ins: Disposing of Preservative-Treated Wood

We all know where to recycle our empty bottles, cardboard boxes, and plastic packaging, but where does preservative treated wood go?

Treated wood is not listed as a hazardous waste under Federal law, and it can be disposed of in any waste management facility authorized under State and local law to manage such material. State and local jurisdictions may have additional regulations that impact the use, reuse, and disposal of treated wood and treated-wood construction waste, and users should check with State and local authorities for any special regulations relating to treated wood.

FPL's Steve Halverson working in the pressure treatment facility.

FPL’s Steve Halverson working in the lab’s pressure treatment facility—but where will this treated wood end up?

Treated wood must NOT be burned in open fires or in stoves, fireplaces or residential boilers, however, because the smoke and ashes may contain toxic chemicals. Treated wood from commercial and industrial uses, for example, from construction sites, may be burned only in commercial or industrial incinerators in accordance with State and Federal regulations.

Spent railroad ties treated with creosote and utility poles treated with pentachlorophenol can be burned in properly equipped facilities to generate electricity. As fuel costs and energy demands increase, disposal of treated wood in this manner is becoming more attractive, however, it poses more challenges with wood treated with heavy metals (which remain in the ash for further processing).

Researchers have demonstrated that wood treated with heavy metals can be chipped or flaked and reused to form durable panel products or wood-cement composites.

Techniques for extraction and reuse of the metals from treated wood have also been proposed, including acid extraction, fungal degradation, bacterial degradation, steam explosion, or some combination of these techniques. All of these approaches show some potential, but none are currently economical. In most situations, landfill disposal remains the least expensive option.

Reuse of treated wood may be a viable alternative to landfill disposal, and in many situations, treated wood removed from its original application retains sufficient durability and structural integrity. Generally, regulatory agencies recognize that treated wood can be reused in a manner that is consistent with its original intended end use. The biggest obstacle however is the lack of an efficient process for collecting and sorting treated wood.

The city of Baltimore, Maryland, has 16,000 vacant homes. Reclaiming materials through deconstruction and establishing market outlets can create value where not currently exists.

The city of Baltimore, Maryland, has 16,000 vacant homes. Reclaiming materials through deconstruction and establishing market outlets can create value where not currently exists.

Researchers at the Forest Products Laboratory (FPL) hope to change this in the future. Pilot studies have already been conducted to develop cost-effective methods to collect, sort, and reuse wood (including treated wood) from urban areas. In addition to conserving resources and helping the environment, these methods have the added benefit of stimulating local economies with new jobs and industries.

Disposing of treated wood in a responsible way may not be as simple as a trip to your local recycling center, but it is still an important part in the life-cycle of the material that must be considered to ensure wood remains a sustainable, environmentally friendly resource.

Wood Preservatives: New Report Explores Directions and Possibilities

A new report has just been published: Wood Protection Research Council, Research Priorities 2013

In this report, authors Carol A. Clausen, Frederick Green III, Grant T. Kirker, and Stan T. Lebow report on findings and recommendations from the Wood Protection Research Council.

Why wouldn’t a homeowner want to build with wood? Sometimes homeowners do not select wood as a building material because of its vulnerability to biodeterioration by fungi and insects under certain conditions of storage and use. These limitations are also a prime cause of user dissatisfaction. Therefore, efforts to protect wood from biological degradation are among the earliest research at the Forest Products Laboratory. This research has successfully reduced the demand for lumber from our National Forests by reducing the need to repeatedly replace existing wood products.


The cycle of wood harvest, research, and use protects our natural resources.

Wood protection has undergone dynamic changes since the industry voluntarily withdrew chromated copper arsenate (CCA) from most residential uses and new products were introduced to the marketplace. According to the Environmental Protection Agency (EPA), “CCA is a chemical wood preservative containing chromium, copper and arsenic. CCA is used in pressure treated wood to protect wood from rotting due to insects and microbial agents. EPA has classified CCA as a restricted use product, for use only by certified pesticide applicators.”

Obviously, alternatives for wood protection are needed. However, to bring a new preservative to the marketplace, a considerable amount of performance data needs to be obtained. Current laboratory methodologies to determine the durability of test specimens are insufficient, and long-term field testing is required to ensure that a treatment is effective.

Improved accelerated test methods to predict performance would reduce the time needed for the development and acceptance of new preservatives. Potential improvements for accelerated testing may include selection of test fungi, techniques to detect incipient stages of fungal decay, methods to properly assess durability of wood plastic composites use of rapid laboratory bioassays for screening, and field tests that could measure loss in mechanical properties and statistical analysis.

Possibilities and research opportunities abound. For instance, protection systems could be targeted to specific problems. With nanotechnology at the forefront, novel advances in wood protection could replace the broad spectrum biocides traditionally used to inhibit decay fungi. The most logical approach to develop targeted biocides is to take advantage of unique physiological attributes of decay fungi, such as their ability to sequester metals through production of oxalic acid or natural tolerance to preservatives. Discerning and describing these mechanisms may enable us to design specific, targeted inhibitors to control decay and circumvent preservative tolerances that are common in brown-rot basidiomycetes.

This report summarizes presentations and comments from the inaugural Wood Protection Research Council meeting. Research needs for the wood protection industry were iden­tified and prioritized. Methods for successfully addressing research needs were discussed by industry, academia, and association representatives.




Patents? From Dead Trees?

You may be surprised at how many technologies from FPL research get patented. What is the value of that? Patents are an effective mode of technology transfer, as they make technologies more appealing to the marketplace due to the exclusivity they offer. Technology transfer leads to increased productivity, increased industrial innovation, enhanced U.S. industrial competitiveness, job creation, and improved and lower cost public services.


Patent Advisor Janet Stockhausen and her team ensure that this technology transfer happens each year. In addition to the work of JY Zhu listed in a previous post, below are the patents that came from FPL this year.

Patents and Licenses

Maria G. Rojas, Joan A. Morales-Ramos, Frederick Green, and Thomas A. Kuster  – Naphthalenic Compounds as Termite Bait Toxicants (Patent No. RE44,543, Issued 10/22/13)


Wood attacked by termites.

Jeffrey P. Youngblood, Yizheng Cao, Robert J. Moon, William J. Weiss, and Pablo D. Zavattieri – Cellulose Nanocrystal Additives and Improved Cementious Systems, licensed by Purdue Research Foundation

Jilei Zhang, Zhiyong Cai, and Sung Phil Mun – Methods of Synthesizing Graphene from a Lignin Source, licensed by Mississippi State University

Keeping Wood Dry Isn’t Always Enough: Beware of Dry Rot

Build Green: Wood Can Last for Centuries by Carol Clausen and Samuel Glass tells us that most wood-decay problems only occur when decay fungi grow in wet wood. But one kind of fungus is uniquely capable of transporting its own water from a source of moisture (usually soil) into wood that is typically too dry to decay. While decay by such water-conducting fungi is uncommon, when it occurs, it is devastating.


Dry rot starts when an infected piece of wood forms a bridge between soil and other wood in a house (Photo by Carol Clausen, FPL).

Large areas of flooring and walls can be destroyed each year unless the fungus is stopped. Ironically, it may be the easiest fungus to prevent or control. Unlike typical decay fungi that start growing from airborne spores, water-conducting fungi usually start growing from previously infected lumber that forms a bridge between the soil and other wood in the house. This can happen if old, discarded beams that have been lying on the ground are used in home repairs or additions; new wood has been improperly stored in contact with soil; or infected wood waste is used as fill under a porch or addition. This type of decay can be stopped by simply breaking the contact between susceptible wood and the source of moisture. Once the water supply is broken and the infected wood dries, the fungus will die.

Good news for the homeowner: a potentially destructive source of rot is easy to control with attention and care.