Tapping into the “Wonderful World of Wood”

by Riley Steinbrenner
At the last Science on Tap session of the summer at Minocqua Brewing Company Wednesday night, Michael Wiemann of the USDA Forest Service Forest Products Laboratory talked about his journeys into the “wonderful world of wood.”
Wiemann, a wood technologist and botanist, started his career working to help create an identification key for tropical wood species in Costa Rica.

Michael Wiemann speaking to a full house at Minocqua Brewing Company. Photo by: Riley Steinbrenner

He said he owes a lot of credit to the university students from the area who provided him feedback and did not hesitate to let him know when they thought a wood-type was misidentified. In fact, this is a point that Wiemann touched on frequently during his talk.
“When you work with other people you find that some things don’t make sense,” he said about his experience. And since DNA sampling of dead trees does not yet exist for identification purposes, Wiemann noted later in his talk, it is important to work with other individuals to accurately name a species.
He also helped identify wood species in Ethiopia early in his career. At that time, in the late 1960s, only four percent of the land was forested, so creating an identification key was necessary to preserve the resource and maximize its utilization.
During his second visit to Ethiopia to collect samples of trees stones, or pieces of petrified wood, he recalled the enthusiasm expressed by local children.
They shouted, “Gold! Gold! Gold!” when they saw him excavating, wondering why he would be gathering some “rock” if it was not of any value.
“It was really great to see their reactions when they realized the tree stones were actually wood,” he said.
Later in his career, Wiemann spent time identifying endangered species of wood in Central America, and ensuring that the wood was used sustainably and was not exploited or sold illegally.
Now working for the USDA’s Forest Products Laboratory in Madison, he deals with endangered wood species quite often and hopes that identifying these types of wood will help “catch those who are exploiting it and [ensure] those who are using it legitimately.”
Michael Wiemann shows off a cross section commonly used by the Forest Products Laboratory to observe the cells that make up wood. Photo by: Riley Steinbrenner

Some species of wood are prohibited from trade completely because of their vulnerability, such as Brazilian rosewood and Caribbean mahogany.
The event closed with a thought-provoking question from the audience that “stumped” Wiemann: “Where did trees originate?”
Wiemann guessed somewhere in the Earth’s mid-latitudes, with differing environments that are close enough to “spur diversity.” He recalls being stationed in Germany during the Vietnam War and noticing the lack of variety among tree species.
The first trees probably originated in North America, he said, where it is more diverse compared to Europe in terms of its natural landscape. And when it comes to how these trees in North America will be affected by climate change in the future, Wiemann remarked, the real question is “how fast” will trees need to change to adapt to new conditions.
And those conditions aren’t just limited to surviving hotter temperatures or drier conditions, he said. For example, increasing global temperatures have caused the nooks and crannies in the bark of many tree species to expand, creating spaces for harmful insects to inhabit, he said. And acid rain, which is caused by release of dangerous toxins and pollutants in the atmosphere, also continues to pose a problem in weakening trees.
Ending on a more positive note, Wiemann reassured the Lakeland audience that their wooden recreational boats will stand the test of time for a while, since they are commonly made up of teak or mahogany, two “extremely durable” types of wood.
With a promising future for the Northwoods’ favorite pastime, it’s no doubt Wiemann brought the audience a better appreciation for the “wonderful world of wood” around us!
The next Science on Tap session about the future of farming in Wisconsin will be held on September 6th at Minocqua Brewing Company.