Abstract Bark beetles (Coleoptera: Curculionidae: Scolytinae) have been considered a primary threat to forests throughout the northern hemisphere. Although tree mortality to bark beetles often detracts from forest management goals, the natural role of bark beetles is canopy opening, thinning, and diversification of stand structure and composition, effects that contribute to some ecosystem services in forests managed for multiple uses. Strategies to prevent bark beetle outbreaks exploit their sensitivity to host tree condition and spacing and their reliance on pheromones to attract sufficient numbers to overwhelm tree defenses. Tree species selection at planting or through selective thinning can favor tree species that are more tolerant of site conditions and resistant to bark beetles. Pre-commercial or commercial thinning improves tree condition and creates barriers to beetle population growth and spread. Remedial options include salvage harvest, pheromones for trap-out or disruption of host location, and white paint to disrupt the dark silhouette of the tree bole. Given the labor costs and trade-offs among tactics and the marginal profitability of fiber and timber production, harvest in advance of, or salvage harvest after, bark beetle attack often is the favored management strategy. However, this strategy is not as appropriate in public forests managed for values provided by older, more vulnerable trees. High-value sites for cultural values or endangered species protection may require use of more expensive management options.
摘要 小蠹蟲 (bark beetle) (鞘翅目：象鼻蟲科：小蠹亞科) 被認為是威脅整個北半球森林的主要害蟲。儘管小蠹蟲造成的樹木死亡率往往會減損森林管理的目標，但是小蠹蟲具有一些天然的作用，它們能夠使林冠疏開、疏伐及林分結構和組成多樣化，這些作用能夠為多目標利用的森林管理提供一些生態系統服務。預防小蠹蟲大發生的策略乃利用其對寄主樹木的條件和間距的敏感性，及其依賴費洛蒙誘引足夠數目的小蠹蟲來壓制樹木的防衛。種植時樹種的選擇或選擇性疏伐都有助於樹種更能容忍生育地條件及抵抗小蠹蟲。早期商業性疏伐或商業性疏伐可以增強樹木的條件，並創建甲蟲族群增長和擴散的障礙。補救措施包括殘材伐採、費洛蒙誘殺，或破壞其對寄主的定位，及樹幹塗白漆以消除樹幹較暗的輪廓。基於人力成本以及採用的方法與纖維和木材生產的邊際利潤之間的權衡，在小蠹蟲攻擊前伐採，或在攻擊後殘材伐採，都是可行的管理策略。然而，此策略不適用管理公有林中價值高但樹齡大及較脆弱的樹木。具文化或瀕危物種保護的高價值生育地，可能需要使用更昂貴的管理措施。
| Key words: Scolytinae, disturbance, population dynamics, ecosystem services, host density | | 關鍵詞: 小蠹亞科、擾亂、族群動態、生態系統服務、寄主密度。 |
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