Managing for a whole forest
by Peter Donovan
JOSEPH, OREGON--For Bob Jackson, the most important factor in forest management is the direction, not the speed or efficiency. Results are created one day at a time.
Since they bought the land in 1970, Bob Jackson and Leo Goebel have been managing 160 acres of Douglas fir, white fir, Ponderosa pine, and larch (tamarack) on the north slope of the Wallowas. The management style they have developed here unites high biodiversity with outstanding production of merchantable logs. "Our forest-management philosophy is based on the premise that a healthy forest is a complete forest."
Biodiversity and production
Both men have spent their careers in the woods. They have had a chance to observe the consequences of all types of forest management, and to observe ecological succession in a variety of forest settings.
Bob Jackson, who attended Iowa State in the 1940s, says that the most important (and hardest) course he took there was plant physiology. He points out that 95 percent of a tree's production is derived from biological processes such as photosynthesis, decay, and respiration. Most of the weight of a tree comes from the atmosphere; only a small fraction is derived from soil minerals. It is the fungi, bacteria, and other organisms that make up the soil food web, in the upper layers and surface of the soil, that make a forest possible.
Bob Jackson arranges limbs so as to promote decay, conserve moisture, and provide wildlife habitat.
Says Leo, "we all know that manure is fertilizer. So by having habitat for the chipmunks, the pine squirrels, or the voles, rabbit, and deer, you get their manure--and that's fertilizer for these trees. If it's too open, or if you burn up these brushpiles and all this litter, you're destroying the habitat for the chipmunks and all the other fine mammals." He points out that one pellet of vole manure can contain up to 25,000 nitrogen-fixing bacteria. Voles require cover, and typically range only 40 feet.
"There's a tremendous difference when you've got a forest that's fully stocked, with lots of shade and habitat, and biodiversity. If you have a plantation with trees in a row, and go out there and fertilize and cultivate them, I don't think you'll grow as much volume as you will by letting them grow naturally."
Bob and Leo keep some standing dead trees (snags) as habitat for wildlife. Thirty-one species of birds have been seen nesting on the property, and bobcat and cougar are spotted periodically. "The ants are extremely important in controlling the budworm, tussock moth, and so forth," Leo says. "So if you don't have habitat for the ants, then you don't have the habitat for the birds, which feed on the ants. The birds and the ants control a lot of your insects. You can get into a lot of problems when you don't keep a complete forest, and manage for that."
In addition to the wildlife, insects, and underground fungi and microorganisms that are so essential to growing trees, Goebel and Jackson point out how high biomass in standing timber--roots, canopies, trunks--is crucial to continued high production of merchantable wood fiber.
Leo Goebel with a cross section showing the board footage at different diameters.
Annual growth rings show that the volume of fiber a tree produces each year, all other things being equal, is proportional to the square of the tree's diameter. Thus a tree that increases its diameter by 22 percent has added volume by 50 percent. The usability and value of the lumber also increases with diameter. The lesson, they say, is to grow these trees as long as you can. A site with plenty of large mature trees produces the most volume and grade.
The soil surface
The tree farm's soil is mostly rock-laden outwash from the steep mountain slopes above. Leo will point to a rock and name the geological formation from the mountain above from whence it came.
"This is all rock here. It's all gravel, outwash. You don't need a lot of deep soil for trees. What you need is to leave the boughs, the needles, the cones and stuff to rot and develop their own process there."
Jackson spends considerable time and hand labor maintaining nutrient cycling and wildlife habitat. The soil surface is the crucial interface. "Most rural people know that fenceposts rot off at ground level or just below. This is where moisture and oxygen are available." To promote the rapid decay of woody material, Jackson works to get most slash flat on the ground, where it will be less likely to dry out, and where it will cover and contribute to the soil food web.
He stacks boughs and limbs to make "wildlife structures" that provide cover for small animals, such as voles. These mounds also help retain moisture, which will enable the debris to decay. With such attention to decomposition of woody material, fuel loads are reduced, and there is little need for burning.
Their soil is well covered. "When we've had spring rains, down in the fields [below the tree farm], there'll be water that's running off. Up here it isn't. Most of our moisture loss is at the water table level, or else it's in the vegetation."
Bob also points to less risk and danger from fire, "because we've got the soil protected and have moisture retention. By taking care of the land, keeping things green, keeping your moisture, you're cutting a couple or three weeks off the worst part of fire season." He points out that the moisture-holding capability of decayed organic matter is an order of magnitude greater than that of mineral soil. Their canopy of mature trees helps create shade, elevate humidity, retain moisture, and thus promote nutrient cycling and decay. Their grass--which is not grazed by livestock--stays green all summer.
In the summer of 1997, heavy rains brought flows of mud and rocks down onto the tree farm from the sparsely vegetated mountain slopes above. A few trees were downed or damaged by rocks. Where hardened mudflows, one or two feet deep, entomb the root area, trees are now losing vigor and dying some two years later. Leo points to this as dramatic evidence that trees depend on the biological activity of the top, aerated layers of soil.
Their fully stocked, uneven-age, mixed-species stand of timber on the property has sustained an average harvest level of about 450 board feet per acre per year. Were the rest of Wallowa County's timberlands as productive as the Goebel-Jackson property, sawmills would be opening instead of closing.
Most logging and forest management, Leo Goebel points out, has tended to be based on the economics of harvest and delivery to sawmills, rather than on the economics of production. Once the railroad arrived in the Wallowa Valley (1908), and export of lumber became possible, says Leo, "they high-graded it. They took the biggest, and the best, and that was where the money was. That has gone on up to the present day."
"Boise Cascade is a corporation. They have a board of directors. They hire a CEO. The CEO hires foresters and mill managers. Everyone's job is to make money for the corporation--for this quarter, for this biennium, so that the stockholders get their return. The way to make money is to cut these trees as cheap as you can, and put them into the mill as cheap as you can. The cheapest way is to cut the big logs, and to cut as many per acre as you can. They have more volume. You're going to take the big trees, and the high-quality trees."
"The [sawmilling corporations] bought the land, logged it, sold the land, and they took their money and left. That's our American way, our capitalistic system. We're making money. But what we've done, is we've drastically lowered the productivity of the land. We've taken off the biggest trees, the genetically superior trees, the healthy trees."
"Much of the land today only has small trees on it, probably less than 25 percent of its potential. A lot of it won't grow a merchantable tree in 30 years. Your land is not producing near what it could be producing if it was fully stocked with a mixture of sizes and species. If you don't have the trees there to shed the needles, cones, the moss, lichen, twigs and so on, that's the annual fertilizer, which can run a ton and half to two ton per acre per year."
Short-term economics and long-term economics are two different things. "People would say, cut these trees and put your money in the bank or put it in stock--you could make more money. Well, you can on a short term. But on a 20-year term or a 50- or 100-year term, I doubt it. If trees are healthy and have room to grow, you shouldn't be cutting them."
A fully stocked stand
After a clearcut or most forest fires, says Goebel, "you've got nothing left to manage." These areas lack everything that Goebel and Jackson have on their tree farm--a fully stocked stand, ample soil cover, moisture retention, rapid decay, and high biodiversity in the soil.
"To get maximum productivity out of the land, on a sustained basis, you've got to keep it fully stocked," Leo says. "What is ‘fully stocked' is a matter of judgment. You need some openings, some biodiversity. But on 80 to 90 percent of that land, it can be fairly heavily stocked."
Logging--mostly done with a small crawler tractor on the gently sloping property--is single-tree selection, mostly salvage and pre-salvage. That is, most trees that are no longer producing marketable fiber at a good rate are cut and sold as logs. The capacity of what is left is of more importance than what the harvest is. They leave their high-producing, genetically superior, healthy trees--the opposite of what more traditional logging has done.
Most of the regeneration is natural, and slow. In more conventional management, the need for immediate regeneration after clearcuts has led to some expensive practices such as burning, brush clearing, repeated hand planting, aerial fertilization, and thinning with chainsaws. In the short-term accounting of conventional timber management, regeneration is rarely accounted as a cost of harvest.
"They want trees now, this year, next year," says Leo. "If you're fully stocked, you're in no hurry to get trees. You can can wait and let Nature put them in here. If you're going on a 300 to 400-year cycle, what if I didn't have any new trees here for 20, 30 years? So what? If you have one seedling per acre per year, that's all you need."
"This 200-foot square right here is growing 648 board feet per acre per year, because of these bigger trees. And if I don't cut these trees, they could grow another 100 years, easily. These seedlings here could get to be as big as they are now. I'm fully stocked."
Fire or ground disturbance encourages tree seeds to germinate. "If you thin by hand, and keep it stocked, there's no reason to run a fire through. You might get rid of a fuel load, but you'll end up with a thicket of little trees that need to be thinned. You're burning up your fertilizer, your habitat for the chipmunk and the squirrel."
In cases where timberland has been neglected or abused, projects such as thinning tend to become priorities. Once the land is productive, and properly stocked with mixed ages and species, Bob Jackson says that the manager can turn to the maintenance of biological processes--which is usually not so arduous. Focusing on maintenance rather than projects enables him to have a sense of continuity, a sense of direction in management.
Bob Jackson with a pine seedling that has sprouted on a rotting stack of fenceposts, contradicting the conventional wisdom that pine seedlings require mineral soil in order to thrive.
Doing much of the maintenance work by hand, Bob says, avoids the unintended consequences--such as soil compaction or damage to living trees--that tend to come with the use of machinery. It also promotes observation, reflection, physical and mental health, and enables him to continuously refine his silviculture. Recordkeeping and observation have contributed greatly to the evolution of Goebel and Jackson's management approach.
They have learned that the wealth they generate (as well as long-term community stability) is a function of maintaining effective biological processes on their land. Jackson points out that concepts of desired future condition that neglect the basic ecosystem processes by which they are achieved have little value.
Their work has not gone without recognition. In 1984 and again in 1991 they won the Oregon Tree Farmer of the Year award. In 1992 they won the Western Regional top award. Thousands of people have gone on tours of their tree farm.