Conservation of old-growth forests has become an increasingly important objective of Forest Service managers over the last three decades. The US Forest Service recently made changes to policies that prohibit cutting of live trees >53 cm (the “21-inch rule”). We review the disturbance ecology of dry and mesic old-growth forests of Oregon and contrast conservation policies for these two forest types. We describe the development of age-based alternatives to the 21-inch rule on the Klamath Reservation and in the Malheur National Forest in eastern Oregon. We conclude by outlining an adaptive management strategy to conserve dry forest old growth that seeks to restore the ecological processes that perpetuate old tree populations over time. We argue that what is good for dry forest ecosystems is good for dry forest old growth, especially in the face of changing climate and disturbance regimes.

中文翻译：

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俄勒冈州东部干燥森林老生长的保护

在过去的三十年里，保护原始森林已成为林务局管理者日益重要的目标。美国林务局最近对禁止砍伐大于 53 厘米的活树（“21 英寸规则”）的政策进行了修改。我们回顾了俄勒冈州干旱和中生林的扰动生态，并对比了这两种森林类型的保护政策。我们描述了在克拉马斯保护区和俄勒冈州东部的 Malheur 国家森林中对 21 英寸规则的基于年龄的替代方案的发展。最后，我们概述了一种适应性管理策略，以保护干燥的森林老树生长，旨在恢复随着时间的推移使老树种群永存的生态过程。我们认为对干旱森林生态系统有益的东西对干旱森林的老生长有益，