FPL Researchers Honored by Forest Stewardship Council

The Forest Stewardship Council, the world’s leading forest certification system, announced its 2017 FSC Leadership Awards in a celebration at Greenbuild. Recognizing enduring commitment to forest conservation, the award shines a light on people, companies and buildings that are breaking new ground and promoting responsible forest management.

The Forest Products Laboratory’s Center for Wood Anatomy Research was honored with a FSC Leadership Award “for applying state-of-the-art forensic wood science to verify the accuracy of FSC claims on more than 1,000 products annually.” Continue reading

The Beauty of Holiday Trees is More Than Bark-Deep

If you are one of the many people who head out into the woods, to the tree farm, or to the corner lot each year to find the perfect holiday tree, you know what your favorite tree looks like on the outside. But do you know what it looks like on the inside and magnified 400 times?  FPL’s Center for Wood Anatomy Research can give you a peek at the secret inner workings of several of the most popular holiday tree species in the United States.

The True Firs

For some time, the single most popular holiday tree in the U.S. has been the Fraser Fir. The Fraser is much loved for its persistent green and silver needles, good form, and pleasant odor.  Closely related to Fraser Fir are several other true firs, including Balsam Fir, White Fir, and Noble Fir.

The microscopic wood anatomy of the true firs as a group is fairly consistent, with the primary differences being the presence of small calcium oxalate crystals in the ray cells of species in the white fir group.  Crystalline materials have the physical property of birefringence, which is a bending of light – this lets the crystals shine out against a black background when viewed with polarized light microscopy and shows off some of their hidden beauty.

(L) Radial section of white fir showing calcium oxalate crystals (arrows). (R) Polarized light micrograph of the exact same cells as on the right. Note the crystals (arrows) shining out against the dark background.

The Pines

Second only to the true firs, pines are among the most classic holiday trees regardless of where in the country you live. Three species top the list: eastern white pine; Scots pine; and Virginia pine.

Eastern white pine is beloved for its long, soft needles borne in clusters of 4-5 and its graceful branches.  Under the microscope, white pine wood is a flagship example of the white pine group; in fact, in colonial times the British harvested mature trees as prime mast wood for their navy (pun intended).

Radial section of eastern white pine showing classic white pine features: smooth ray tracheids (arrows) and fenestriform cross-field pits (arrowheads).

Radial section of eastern white pine showing classic white pine features: smooth ray tracheids (arrows) and fenestriform cross-field pits (arrowheads).

Scots pine, a European native grown in plantation in the U.S., is favored for its short, twisted needles and slightly orange bark. From a wood anatomical point of view, it is an archetypal member of the red pine group, and its wood cannot be definitively separated from North American red pine, much to the dismay of many an antique dealer.

Radial section of Scots pine showing classic red pine features: dentate ray tracheids (arrows) and fenestriform cross-field pits (arrowheads).

Radial section of Scots pine showing classic red pine features: dentate ray tracheids (arrows) and fenestriform cross-field pits (arrowheads).

Virginia pine grows natively in the American southeast, but its closest relatives are not other Southern pines, but rather Western yellow pines.  Despite the long distance to its nearest kin, it is a well-loved alternative to Scots pine, and is a perfect example of all its relatives in the larger yellow pine group to which it belongs.

Radial section of Virginia pine showing classic yellow pine features: dentate ray tracheids (arrows) and pinoid cross-field pits (arrowheads).

Radial section of Virginia pine showing classic yellow pine features: dentate ray tracheids (arrows) and pinoid cross-field pits (arrowheads).


Not actually a true fir, but instead a member of a completely different genus, Douglas-fir is a full, stately holiday tree valued for its ability to fill large, open spaces. Douglas-fir is an eye-catcher beneath the bark and seen with the microscope, too – helical thickenings are abundant in the earlywood tracheids but not the latewood tracheids, and set apart the wood of this tree from almost all other conifers.

Radial section of Douglas-fir showing the abundant helical thickenings in the earlywood tracheids (arrows) and the absence of helical thickenings in the latewood tracheids (arrowheads) on the far right.

Radial section of Douglas-fir showing the abundant helical thickenings in the earlywood tracheids (arrows) and the absence of helical thickenings in the latewood tracheids (arrowheads) on the far right.

As you decorate your tree this year, take a moment to appreciate the minute, inner beauty and splendor waiting to be seen just beneath the surface.


Contributed by:  Alex C. Wiedenhoeft, Adriana Costa, Rafael Arévalo, Richard Soares, and Mario Ramos.

Philippine Partnership : FPL Hosts Southeast Asian Scientist

The Center for Wood Anatomy Research (CWAR) at the Forest Products Laboratory (FPL) is pleased to host Mr. Mario Ramos, Senior Science Research Specialist from the Anatomy and Forest Botany Section of the Forest Products Research and Development Institute (FPRDI), Department of Science and Technology, Philippines.

FPRDI main image

The Forest Products Research and Development Institute, Los Baños, Laguna, Philippines. FPRDI is one of just a handful of state-funded forest products labs. Photo credit FPRDI.

Ramos’ official program title is “Training Course on Wood Anatomy, Identification, and Imaging” and includes training and preparatory work toward long-term cooperation with CWAR’s XyloTron wood identification program.

The XyloTron is a machine-vision-based wood identification system that uses a custom-designed wood imaging device (the XyloScope), image analysis, and statistical processing software run from a laptop/netbook. With it, users can identify over 150 species of wood more accurately than trained law enforcement personnel. The technology could help combat the global problem of illegal logging by empowering law enforcement agents to make field identification of wood.

In addition to learning how to construct and maintain a XyloTron, Ramos will begin to prepare and image the CWAR’s extensive holdings of Philippine woods, and when he returns to FPRDI with a XyloTron, he will carry on the work there.


Mario Ramos at his microscope in the Center for Wood Anatomy Research, Forest Products Laboratory in Madison, WI. Photo credit R. Soares.

“I am very fortunate and privileged to be part of FPL’s Center for Wood Anatomy Research team,” said Ramos. “While brief, my training at FPL’s CWAR will definitely have great impacts particularly on improving the wood anatomy laboratory facilities and the services we offer at FPRDI. I am excited for my involvement with the machine vision project given its impacts on the preservation of threatened and/or endangered wood species in the Philippines.”

“The Philippines is extremely rich in natural resources, especially timber, and is one of the most important biodiversity hotspots in the world,” said FPL’s Alex Wiedenhoeft, Research Botanist and Team Leader for the CWAR.  Anything science can do to extend the forest resources, encourage wise use and good management, and prevent illegal logging is time well-spent.”

Ramos and Wiedenhoeft had corresponded for a number of years, always with the hope of being able to arrange a scientific exchange and initiate a cooperative research program. The cooperation was made possible by a Philippine training grant program and a Memorandum of Understanding (MOU) between FPL and FPRDI.

The MOU establishes a framework for partnership in range of research areas in addition to wood anatomy, including cellulose nanomaterials; wood composites; wood decay and preservation; lignin and products from lignin; fire and fire testing; life cycle assessment; non-destructive testing; and, other areas of mutual interest.


The Center for Wood Anatomy Research team that Mr. Ramos has joined. From the left, Alex C. Wiedenhoeft, Research Botanist and Team Leader; Adriana Costa, postdoctoral visiting scientist from São Paulo, Brazil; Richard Soares, visiting scientist from São Paulo, Brazil; Mario Ramos, visiting scientist, FPRDI, Philippines; Rafael Arévalo, postdoctoral visiting scientist, Bogotá, Colombia. Photo credit A. Wiedenhoeft.

“FPL is pleased with the success of our initial scientific exchanges, and we hope that this cooperation and our MOU paves the way for additional exchanges and cooperative work,” said FPL’s Michael Ritter, Assistant Director for Wood and Wood Products.

Mr. Ramos’ Anatomy and Forest Botany Section is analogous to the CWAR, and FPRDI, established in 1954 as the Forest Products Laboratory in the Bureau of Forestry, was modeled in part on FPL’s organization and mission. FPRDI, like FPL, is one of just a handful of national forest products labs around the world that still enjoy state funding.

Contributed by Alex Wiedenhoeft

LOGJAM: Art Exhibit Inspired by Forests

Logjam_slideA new art exhibit at the Overture Center’s James Watrous Gallery in Madison, Wis., brings prints and sculptures together to a magical place where art, science, and history collide.

LOGJAM features the work of three artists: Brenda Baker, Kevin Giese, and Mark Iwinski. According to the Gallery’s website, the artists’ “sculpture and prints inspire reflection on environmental restoration and the health of our forests. Through photographs, artifacts, and text, the exhibition also considers the legacy of the Wisconsin cutover, the rise of industrial forestry, and the development of more sustainable forestry practices.”

“Interpretive sections will include images, artifacts, and texts that evoke the logging era and the subsequent rise of ‘industrial forestry.’ A group of folk art objects and photographs that represent early Wisconsin loggers, logging equipment, and lumber operations will be on view, along with samples from the USDA Forest Products Lab’s (FPL) renowned wood anatomy collection. Objects that reflect today’s interest in sustainable forestry, urban wood products, and ‘whole tree’ lumber will also point to current issues in forestry and timber usage.”

If you’re in the Madison area, a visit to the gallery is worth your time. If you’re afar, the exhibit’s flickr site is a great way to catch a glimpse of these talented artists’ fine work. FPL’s contribution can be seen in this flickr gallery from the exhibit’s opening night. Can you find it? (Hint: It looks like an interesting variation on the classic card catalog, if you’re old enough to know what that is!)

Women’s History Month: FPL Remembers Catherine Duncan

Lab Notes remembers another pioneering woman scientist: Catherine Gross Duncan. Duncan received her A.B. Degree in botany from the Depauw University in 1931. She went on to earn her M.S. and her P.h.D. from the University of Wisconsin in 1933 and 1935, respectively.

In December 1942, she joined the Forest Products Laboratory (FPL) in cooperation with the University of Wisconsin. Originally, she was recruited by the Lab to aid in the war effort. Duncan stayed after the war for the remainder of her career. She eventually rose to the rank of principal pathologist at the FPL in the Wood Fungi and Insects Research, where she served until her death in 1968.


Ralph Lindgren and Catherine Duncan inspecting the growth of a fungus that is part of the fungi collection.

During her career, Duncan published over 40 papers examining various aspects of wood decay fungi. A majority of her work surrounded the quality and improvement of wood preservatives. Duncan was also involved with the dissertations of 30 students while she worked at FPL. Students noted that “It was always a challenge to meet her standards for rigor and proof in research”.

Early in her career, one of the first projects she completed for FPL was to examine the natural resistance of decay from different species of trees. In studying these differences, she helped develop the soil-block technique, which allows for wood decay to be studied at an accelerated rate. This technique became especially important when evaluating wood preservatives and their longevity, and is still in use today.


Soil-block tests showing the effects of fungi on a specimen: (A) fungus growing on
untreated wood specimen; (B) fungus fruiting on untreated wood specimen; (C) preservative-treated wood specimen.