What does it mean to cruise a forest with a crystal ball? How exactly does someone perform this seemingly magical process? This can all be explained by Dr. John F. Bell, an expert and influential figure in the timber cruising method called variable plot sampling.
When Bell began his education and his career in forestry, he had not even heard of the timber cruising method that would become a major part of the next 50 some years of his life. He started out as a forestry major at Oregon State in 1942, but his education was abruptly interrupted by WWII.
Bell was in the middle of his freshman year when he was called to active duty as a part of the Enlisted Reserve Corps. He volunteered along with several other Oregon State forestry students to join the ski troops, which became the 10th Mountain Division. He thought this was as close as he would get to forestry in the military. Bell and the other Oregon State forestry students trained for 15 months in the lofty peaks of Colorado, “9200 feet elevation at Camp Hale and up from there,” he said. They were then sent to Texas in the summer heat and humidity. He later became an officer and at the end of the war spent a year in the Philippines.
Bell received his undergraduate forestry degree from Oregon State in 1949, his master’s degree from Duke University in 1951 and his PhD at the University of Michigan in 1970. He worked for 10 years for the State of Oregon Forestry Department. It was during this time, in the 1950s, that variable plot sampling first caught his attention.
At the time, Bell was actively searching for a new, less tedious way to determine volume and value of forest stands. “We tried lots of ideas,” he said, “Then I heard about this forester running around in the woods with a crystal ball,” which turned out to be a wedge prism, a tool used in variable plot sampling. The wedge prism, which looks like a single lens from eye glasses, is used to tell which trees to count and to measure. Bell found that the new technique was simpler to use than the standard method, called fixed area plot sampling, and it yielded results that were just as accurate. Bell said that the greatest benefit to variable plot sampling is that it is so much more efficient. It is so efficient that this technique saves between a third and half the time of the standard method.
Bell introduced the idea of using this revolutionary form of sampling for timber sales to the State of Oregon Forestry Department. It produced such great results, that the State Forestry Department became the first recognized public agency to sell timber based on variable plot sampling cruises.
With the successful results, Bell was asked to assist Lu Alexander, class of 1940, with a variable plot sampling workshop sponsored by the Society of American Foresters and the Oregon State School of Forestry in 1957, to educate professional foresters on the new method. The course has been offered every year since with Bell as the director. He explained, “We’re trying to teach foresters better procedures and more efficient methods of sampling forest stands.” With his former student and OSU alumnus Dr. Kim Iles (BS ’69, MS ’74, Forest Management), he has taught similar workshops in other locations in the United States, Canada, Australia, and Chile.
April 2007 marked the golden anniversary of the workshop, which has now been taught by Bell for 50 consecutive years at OSU. He was recently honored and presented with a plaque by the OSU College of Forestry for his half century of highly distinguished service in outreach education.
Bio of John Bell written by Carrie Breckel, Editorial Assistant, Forestry Communications Group, College of Forestry