Large old growth trees have a certain fascination about them. Perhaps it is their sheer size and the beauty their forms exhibit. Perhaps we are intrigued by the fortitude they display having stood for all those years almost in defiance of Mother Nature and the hardships that the weather has tested them with. Certainly their age is impressive and who has not thought while gazing at a large specimen what is has had pass under its branches. Certainly in the case of my bur oaks I like to believe that it was witness to the herds of buffalo and elk that were numerous in southern Wisconsin at the time of the early explorers. Native Americans would also have passed by in their travels up and down the Rock River.
Years later my interest in trees and the ecosystems they are a part of influenced me to pursue a degree in Forest Management. Immediately after graduation I took a temporary position with the Marathon County Forestry Department. The summer passed quickly and once the job was completed I got the travel Jones. I decided to head west to see what employment opportunities were available which was actually secondary in importance to my desire to see the “big trees” that grew “out west”. I figured that every forester should see these great trees at least once in their lifetime. My first destination was the Giant Sequoia groves of Central California. Amazement is the best expression of what I felt upon actually seeing these huge trees. Thousands of years old, two hundred and seventy-five feet tall and thirty-six feet in diameter at its base the “General Sherman” tree as it is called rendered me speechless. My girlfriend and I stood in front of the tree, circled it, and looked it up and down countless times trying to comprehend its majesty. Hours later it was hard to pull ourselves away from the Sequoias but we had other giant trees to see. Next we visited the Redwood Forests of Northern California and then the Rain Forests of the Olympic Peninsula in Washington State. The awe that we felt in the presence of these stately trees did not diminish with each visit. These ecosystems are rare and precious and should be maintained for our children and our children’s children to experience, which brings me back to the title of this article. I like big trees too but I agree with what Gifford Pinchot our nation’s first forester learned as a student of forestry in Europe before forestry was practiced in America. In the words of his professor, “When you get home to America you must manage a forest and make it pay.” When you examine the rate of return that trees of different diameter classes earn it becomes apparent that big trees do not increase in value at a rate comparable to young vigorous trees. With recreational land taxes (including a lot of forest land) increasing all the time this is of significant interest.
In December of 1891 Pinchot was invited to take charge of the Biltmore Estate Forest and became the first practicing forester in the United States. In his book “Breaking New Ground” Pinchot writes “The lumberman ….regarded forest devastation as normal and second growth as a delusion of fools, whom they cursed on the rare occasions when they happened to think of them. And as for sustained yield, no such idea had ever entered their heads”. The forest provided the early settlers with shelter, food and fuel but also danger in the form of hostile Indians. After a while the settlers came to look on the forest as the enemy. It was a hindrance to progress and needed to be cleared. The forest was generally regarded as inexhaustible however there were a few people who realized that the forests were not going to last for ever and they tried to protect the resource through preservation. One result of their efforts was the creation of the Adirondack State Forest Preserve in New York in 1885 to preserve the forest and water supply. In 1891 an amendment to the State Constitution forbid the cutting of trees which therefore precluded forestry. Commenting on the preservationists efforts to stop the forest destruction occurring Pinchot said “They tried to stop the advance of one of the greatest, most necessary, and thriving and driving of industries simply by explaining to each other how wrong and ruthless it was. Their eyes were closed to the economic motive behind true forestry. They hated to see a tree cut down. So do I, and the chances are that you do too. But you cannot practice Forestry without it.” Pinchot adds “They were utterly right in their purpose but utterly wrong in their method…..they forgot that you cannot beat something with nothing”.
Pinchot realized that in order to save the forests from destruction he needed to put forestry into action and to show the nation that it was possible to harvest trees and still have a forest. Pinchot realized that trees are like crops and forestry is tree farming. One crop follows another and while farmers harvest a crop every year foresters may harvest trees only once every ten, fifteen or more years depending on their objectives and timber types. Just as a well managed farm gets more productive with time so does a well managed forest. Most of today’s forest landowners own their land for a number of different reasons but I doubt if many of them can afford the cost of ownership with out the income derived from the timber growing on the land. Harvesting trees can be a major source of income. While big trees are a thing of beauty they do not pay their way economically. They simply do not bring the same returns to the landowner as a thrifty, younger tree. The table below illustrates the expected rates of return of individual trees based on their diameters at breast height (DBH). The smaller trees experience a greater rate of return than larger trees for a number of reasons. Given sufficient room they are growing faster than old trees and as their diameter increases they are gaining value by becoming higher value products. Trees with diameters at breast height (DBH) less than 10” are valued at pulp and bolt prices. As the tree gains a DBH of 12” the butt log is valued as a small diameter sawlog (providing the surface quality meets the specs.). As the tree’s DBH continues to increase to 14” and up the butt log enters yet another higher valued product class of grade 1 sawlog and veneer log. As the DBH increases to 16” the butt log has reached the size to qualify as a Prime Veneer log. Here again the value increase is influenced more by an increase in grade rather than by an increase in total volume. Once the tree attains a DBH of 18” it has reached it’s highest product value class. The financial maturity of a hardwood tree is obtained when it there is no chance to move up in product class.
If income is an important objective to the forest landowner then they should be aware of the rate of diminishing returns and the size factors that determines the financial maturity of the different tree species in their forest. Just as the farmer harvests his crop when it is mature a forester does the same with trees. Multiple use objectives may include large old growth trees but large trees do not produce the same financial returns as younger trees do. The landowner has to be aware of his objectives and make management decisions accordingly.
I am happy that our government has set aside National Parks and Wilderness areas to preserve some old growth for us to renew our spirits in (most private forest landowners do not have the financial wherewithal or desire to practice non-management). I believe that for forests to survive today’s threats, principally land fragmentation and conversion to other uses they have to pay their way and this includes harvesting trees when they are ripe, following sound forestry practices of course.