University of Idaho Publication
In 1883, when the Northern Pacific Railroad made its way through northern Idaho, western white pines dominated the moist, mid-elevation, mixed-species forests of the Inland Northwest between 2,000 and 6,000 feet. These majestic trees often lived to 350 years but could reach the ripe old age of 400 and even 500 years. They were an integral part of the most productive forests in the region, providing habitat for a highly diverse mixture of organisms, from the smallest microbes to lichens, higher plants, and animals.
On good sites, white pines grew to more than 150 feet tall and 36 inches in diameter. (In 1992, the record-holding western white pine in Idaho was 229 feet tall and 78.7 inches in diameter.) Other species, such as western larch, sometime grew as large, but there were many more white pines, often outnumbering the other trees in mature forest stands. Inland Northwestern forests held the promise of riches for a timber industry that by 1900 had virtually exhausted the supply of old-growth eastern white pine in New England and was rapidly depleting it in the Lake States.
By the late 1960s, our white pine forests in the Inland Northwest were nearly gone, decimated by a combination of white pine blister rust disease, high-grading, overcutting, mountain pine beetle attack, and exclusion of stand-replacing fires. Today, at the turn of a new century, only 5 to 10 percent of the original 5 million acres of white pine cover type in the Inland Northwest still carries a significant component of white pine.
Where white pines used to dominate we now find Douglas-fir, grand fir, and hemlock. Douglas-fir and grand fir are susceptible to a much greater variety of insect and disease problems than is white pine; hemlock is more sensitive to drought and decay. The loss of white pine and the shift in forest tree species has resulted in lower productivity in our forests. Whereas mixed white pine stands commonly produced 50,000 board feet per are, the best mixed fir stands of today are projected to average only half that much. Loss of white pine also means less large wood for fish and wildlife habitat and for nutrient cycling, less old growth, and an increasing risk of particularly severe wildfires.
If we want to reverse this dismal picture, we must restore white pine to our Inland Northwest ecosystems. We cannot rely on natural regeneration to do the job because too little of our native white pine remains to provide a reliable seed source. Only an aggressive planting program, using genetically improved, blister rust-resistant stock and appropriate silvicultural techniques, will ensure the “Return of the Giants.”
(For more information on the white pine, contact the University of Idaho, PO Box 442240, Moscow, ID 83844-2240. (208) 885-7982 and ask for Return of the Giants, Station Bulletin 72.)