Arthur Koehler

Letters to the Lindbergh's

Today is the anniversary of the death of Wood Expert and xylotomist Arthur Koehler.
Xylotomy is preparing little pieces of wood and then examining them under a microscope or microtome. Koehler worked as a chief wood technologist at the Forest Products Laboratory in Madison, Wisconsin.
Koehler's expertise led him to become one of the very first forensic botanists.
When the Lindbergh baby was kidnapped in 1932, a homemade ladder was used to access the nursery.
Koehler, along with 38,000 others, sent letters to the Lindbergh's offering prayers and assistance. Yet Koehler's expertise would become the linchpin to convicting the man accused of the crime, making Koehler one of the world's first official forensic botanists.
Forensic botany is simply using plants to help solve crimes.
Three months after the crime was committed, samples of the ladder were sent to Koehler. Koehler studied the pieces through his microscope discovered that four different kinds of wood were used to make the ladder—Douglas Fir, Ponderosa Pine, Birch, and North Carolina pine.
In an interview with the Saturday Evening Post, Koehler was quoted saying,

“I’m no Sherlock Holmes, but I have specialized in the study of wood. Just as a doctor who devotes himself to stomachs or tonsils … so I, a forester, have done with wood.”

A year later, Koehler was invited to see the ladder in person, and that in-person visit was revealing. Koehler discovered the ladder was handmade. He measured each piece to the nose, getting exact measurements. He understood how each piece was cut, how the pieces would have fit into a car, and then assembled at the Lindbergh home. Incredibly, Koehler was able to determine the origin of the piece of North Carolina pine used to build the ladder - it was sold in the Bronx.
Ransom notes from the case lead police to hone in on the same area. Koehler was convinced the suspect would have the woodworking tools required to build the ladder.
In the Lindbergh case, the wood from the ladder helped identify a carpenter named Bruno Richard Hauptmann. When the police arrested Hauptmann, they not only found $14,000 of ransom money but the evidence Koehler could link to the ladder: the saws used to make the cuts, the particular nails used to build the ladder and a missing floorboard from Hauptmann's attic that was clearly used in the construction of the 16th rail of the ladder.
In fact, when the rail was removed, it slipped perfectly back into place in Hauptmann's attic - right down to the nail holes and nails on the board. Koehler estimated the chances of someone else supplying the lumber for the ladder to be one in ten quadrillions.
Koehler's knowledge and testimony during the trial were vital to Hauptmann's capture and conviction. The "Crime of the Century" solved by carefully studying the only witness - a "wooden witness."
It was Arthur Koehler who said,

“In all of the years of my work, I have been consumed with the absolute reliability of the testimony of trees.
They carry in themselves the record of their history.
They show with absolute fidelity the progress of the years, storms, drought, floods, injuries, and any human touch.
A tree never lies.”

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Arthur Koehler
Arthur Koehler

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