Green island in the sky.

Lush amid spectacular brown canyonlands, the Kaibab plateau is the site of a little-known story of wonderfully successful forest and wildlife management.

The Kaibab National Forest's northern division, located on the north rim of the Grand Canyon, has been a managed forest since the early 1900s. During all that time this chunk of northern Arizona has supported timbering as well as hunting and other recreation. Today the Kaibab has more of everything--more timber, more game, and more recreation--than ever. In fact, a 1989 timber survey shows more trees--and bigger ones--today than the Kaibab National Forest had when it was established in 1909.

If the rest of the world's forests were like the Kaibab, those of us concerned about our planet's climate would have less to worry about, thanks to the ameliorating impact of trees on greenhouse gases.

During my recent visit to this high plateau, where elevations range to over 9,000 feet, the July heat was broken by a violent downpour, thunder and lightning, and finally hail that left the forest floor covered. As the sun broke through the scud, the bed of crystal pellets shone silvery through a wispy fog. The trunks of big ponderosa pines stood brown and warm, topped with a far-off canopy of green. The scene was a snapshot of ethereal beauty to be etched forever in memory. But so, too, are other scenes from these magical woods. The Kaibab is a memorable place.

Early visitors described the forests as open and parklike, easy to ride through, with fine stands of grass for their horses to graze. Ecologists believe fires set by Indians and lightning were frequent enough to prevent forest reproduction under the older trees. The large bands of sheep, cattle, horses, and mules grazed by early settlers also served to discourage seedlings.

President Theodore Roosevelt was well aware of the beauty and productivity of the Kaibab country. First established as the Grand Canyon Forest Reserve in 1893 by Benjamin Harrison, the Kaibab's name was changed by Roosevelt to the Grand Canyon National Game Preserve in 1906.

Roosevelt visited often to hunt the Kaibab's plentiful deer, mountain lions, and other game. In those days predators were hunted hard in order to increase the deer herd and make the range safe for domestic livestock. The effort succeeded beyond anyone's wildest dreams.

President Teddy loved this area so much that a proposal was made in 1906 to name it "The President's Forest," but decorum prevailed, and it actually became the Kaibab National Forest.

In 1919 a big block was taken from the national forest to constitute the core of Grand Canyon National Park. By then mountain lions wwere scarcer, thousands of cattle grazed, the deer herd had mushroomed, and the habitant was severely overtaxed. A browse line was evident, where the deer had eaten everything within reach, so the animals began to diminish in size and number until the herd finally collapsed from starvation. The deer stayed scarce until the habitat was brought back to productivity--a process that took 50 years (see "The Great Kaibab Deer Die-Off: Learning the Hard Way" on page 54).

Today's game managers, though perhaps a bit reluctant to say so, do have the specter of another die-off in the back of their minds, so the deer herd is managed to keep the numbers in balance with the habitat.

Meanwhile, in 1909, a timber survey detailed the presence of relatively undisturbed stands of ponderosa pine, mixed conifers, and pinyon-juniper types. The report describes the forest as a virtually "unbroken body of mature timber."

The description goes on in fact to speak of an overmature forest "rapidly depreciating in quality" and crying out for protection and management: "The old trees are fairly uniformly distributed among the young growth over which they tower with spreading crowns, robbing the growing stock of soil moisture and light and themselves producing little or no increment value. . . . Forest fires have been the cause of incalculable losses both from the quantity of actual timber consumed and the fertility wrung from the soil."

The Forest Service took on the task of managing the timber--in a benign sort of way. The primary form of harvesting from 1909 to the late 1970s was sanitation cutting, removing those trees with a high risk of dying due to disease, insects, damage, or age. What this meant in actuality was a few trees removed from most stands but no heavy cutting in any one stands.

Nevertheless, about two billion board-feet of timber products were removed during that period, and a viable forest-products industry developed. The roads that are the backbone of today's tourism owe most of their existence to those timbering operations.

In the late 1970s, managing forests by the stand replaced managing individual trees. Intensive forest management had come to the Kaibab. Of the North Kaibab's 656,000 acres, approximately one-third (237,324 acres) were now classified as tentatively suitable for the production of timber and other forest products. Of this segment, 57,960 acres are scheduled for "treatment"--thinking and other partial removals but no clearcuts--during the 10-year planning period that began in May of 1988. The trees will be allowed to attain an age of 120 years and a diameter of about 18 inches before final harvest.

Another 36,030 acres--about 15 percent of the timbered area--are now delineated on stand maps as "old-growth." The remaining 55 percent or so is not suitable for timber management. The old-growth feel is extended throughout the whole forest via a managerial guideline specifying that no tree over 42 inches in diameter will be cut.

Current management of the areas designated suitable for timber management is aimed at developing a better mix of age classes in the future. Many of these stands are older and overmature. A properly managed forest should theoretically have a mix of all age classes from seedlings up to mature stands of rotation age, which is set at 120 years. Current logging prescriptions emphasize methods of cutting that encourage reproduction and hence the establishment of younger age stands. Most of this kind of harvesting is by shelterwood methods, which leave a light overstoryo of larger trees to shelter the seedling forests until they are well-enough established to be considered saplings. At present, the only extensive stands of small young trees are plantings in old fire scars where no larger trees survived.

The timber survey conducted in 1989--an even 80 years after the first survey--stunned many people who had watched overt the years as a steady stream of forest products emerged from the Kaibab. The benefits of good stewardship had built up slowly through fire protection and timber management aimed at improving growth conditions. That today's forest is bigger and better is shown by comparing numbers from the two surverys:

     Number of trees per acre
Ponderosa Pine Type     1909    1989
Trees of 1" to 3"      107.04   486.60
  diameter
Trees of 6" to 18"      35.48    67.70
  diameter
Trees of 20" to 30+"     9.84    17.54
  diameter
    TOTAL              152.36   571.84
Mixed Conifer Type
Trees of 1" to 3"      138.08  1422.10
  diameter
Trees of 6" to 18"      40.22   132.00
  diameter
Trees of 20" to 30+"     6.33    11.20
  diameter
    TOTAL              184.63  1565.30

That's a triumph, in black and white, for forest management and fire protection as practiced on the North Kaibab over the years.

The current forest plan projects the production of 610 million board-feet of timber during the 1990s, so the North Kaibab will continue to be the backbone of the local economy. Harvest quantities are predicted to increase, in fact, so the forest industrial economy is expected to remain more than viable.

One fact of the increase in standing timber should not be overlooked or underestimated in importance. Trees serve as a carbon sink--trees are about half carbon by weight--and as such they keep carbon dioxide out of the atmosphere, where it would contribute to the greenhouse effect. The increased tree stocks on the Kaibab are thus playing a role in mitigating possible global warming.

Dr. Richard A. Birdsey, Forest Service expert on the storage of carbon, estimates that each forested acre of the Kaibab has 37.15 more tons of carbon stored as cellulose than were present on those acres in 1909. This estimate is based on the cubic feet of growing stock increased by an appropriate factor to take into account roots and limbs--total biomass.

Multiplying 37.15 tons per acre by the North Kaibab's 237,000 acres of timberland gives a total of some 8.8 million tons of carbon sequestered in standing trees. The significance of this carbon sink is that it represents a total of some 33 million tons of carbon dioxide prevented from entering the atmosphere and contributing to climate change.

In addition to the carbon stored in standing trees, much of the two billion board-feet of timber harvested from the Kaibab over the years is probably still in use as houses, barns, furniture, or other appurtenances of living. That represents an estimated additional two million or so tons of carbon dioxide kept out of the atmosphere.

The prevention of over 35 million tons of atmospheric carbon dioxide is not a traditional way to evaluate the success of a forest-management operation, but in today's world perhaps it should be.

The North Kaibab isn't all that easy to get to. It's in the "Arizona Strip," the part of the state that is sandwiched in by Utah and Nevada. But it has proven to be popular with visitors both as a destination in its own right and as a sidetrip for those going to the Grand Canyon.

Several hundred thousand tourists visit each year, many of them dropping by the Jacob Lake Visitor Center for a guide to recreation opportunities and points of interest. They read about the area's early explorations, ranching and farming activities, mining and lumbering. They find there's lots to see and do: they visit historic sites and enjoy camping, hinking, picnicking, and hunting in this green island in the sky.

But the really interesting story behind the story comes when the visitor observes what an 80-plus-year history of good forest management looks like on the ground.