Forest Dreams, Forest Nightmares: The Paradox of Old Growth in the Inland West

Animals: Domestic and Wild Nature

Animals: Domestic and Wild Nature T rees were not the only things that grew in national forests, much as the Forest Service sometimes seemed obsessed with timber. Under the trees, and in the places where trees did not grow, were grasses and shrubs-and the herbivores, both wild and domestic , that liked to eat them. The Forest Service understood that forage plants as well as trees could become commodities. Managers needed to make sure, therefore, that people put those resources to full and productive use. Timber, grazing, and wildlife policies developed within a similar economic framework that promoted full use of resources, but they veered in different directions during the upheavals of the Great Depression. Timber policy in the 1930s underwent a major shift in focus, as the Depression forced the Forest Service to slow its heavy sales programs. When markets for Forest Service timber vanished, foresters reconsidered their emphasis on heavy sales. Yet the critical assumption underlying heavy sales-that people should put the land to full use, making it as efficient and productive as posSible -changed little. Foresters during the 1930s noticed that intensive sales poliCies had threatened a steady supply of pine for the future. But because they did not question the belief that silviculture could improve forests, they failed to see the ecological effects their policies were having on the forest. In contrast, the Depression forced grazing scientists to pay attention to the ecological havoc their policies had wrought, and range researchers-unlike silvics researchers-eventually came to question the virtues of full prodUctivity . 201 202 ANIMALS: DOMESTIC AND WILD NATURE Bunchgrass Ecology and Grazing Effects Although Indians had grazed great herds of horses in the Blues and across the inland Northwest, two decades of cattle and sheep grazing overwhelmed the effects of 150 years of horse grazing. When Lewis and Clark came through the inland Northwest in 1805, they remarked both on the Indians' horse herds and on grasslands that were still luxuriant after three-quarters of a century of horse grazing.! Seventy years later, when whites first brought cattle and sheep into the region, the range was still among the best in the West. But after the grasslands experienced just a few decades of cattle and sheep grazing, they collapsed. By the time the Forest Service began to regulate grazing in the Blues, immense tracts of native perennial bunchgrasses from British Columbia to Nevada were succumbing to the rampant weed cheatgrass (Bromus tectorum), an invader from Central Asia that made for maddeningly poor cattle forage. Why did the bunchgrasses collapse under cattle grazing, when they had resisted horse grazing for 150 years, and the pressures of native ungulates such as elk, deer, and antelope for millennia? And most puzzling to the whites who watched the changes: Why were the grasslands east of the Rockies in the Great Plains able to resist heavy grazing damage, while the grasslands west of the Rockies changed almost as soon as cattle reached them? Both places were dry; both places were covered mostly with perennial native grasses; both places looked pretty much the same. What in the world was so different? The ecologist Richard Mack has argued that to make sense of these differences, we need to consider the evolutionary history of the two r~gions. The grasslands of the intermountain West had formed quite recently in evolutionary time-only six million years before, when the Cascades and Sierras rose and blocked the Pacific winds. What little rain reached the east side of the mountains fell mainly in the autumn and winter; summers were extremely dry. In contrast, grasslands in the Great Plains evolved millions of years earlier, when the emerging Rockies blocked moist winds from the western oceans, creating a much drier region on the leeward side of the new mountains. Yet even though the Great Plains were quite ANIMALS: DOMESTIC AND WILD NATURE 203 dry, rain fell throughout the spring and summer, during the growing season. Because of their summer rains, the Great Plains could support grasses that were rhizomatous-meaning that they formed a sod, a continuous mat of stems and roots. Sod-forming grasses needed rain during the spring and summer, so summer aridity excluded them from the intermountain West.2 Instead of sod-forming grasses, the intermountain grasslands were dominated by bunchgrasses-plants growing in tufts-with lichens and mosses covering the spaces between the tufts. The bunchgrasses dealt with the summer...