Silvicultural decisions and forest-management practices in Minnesota represent the collaboration and partnership between forest managers from multiple organizations and forest researchers. To better understand current practices, trends, needs, and opportunities, Minnesota has invested in the collection of quantitative data on the application of silvicultural systems and forest-management activities in 1991, 1996, 2008, and 2017. Drawing on those data, the goal of our study is to summarize 26 years of data to characterize and quantify trends in forest-management practices. During this period of time, timberland ownership (acres) has increased, whereas harvested volume has decreased (cords). Across state, federal, county, forest industry, and tribal forest lands, which collectively represent the majority of timberlands in Minnesota, the clearcut system decreased from 91% of the harvested area in 1991 to 72 percent in 2017. In contrast, the proportion of total harvested area as part of shelterwood, seed tree, selection, and thinning treatments all more than doubled from 1991 to 2017. Factors influencing the changes relate to forest health and diseases, shifts in ownership structure, and shifts in organizational policy and/or goals. The factors identified mirror many of the trends forest managers are experiencing in other regions, nationally and internationally.

中文翻译：

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绝迹的下降：森林经营实践的26年变化及其对明尼苏达州的影响

明尼苏达州的造林决策和森林管理实践代表了来自多个组织的森林管理者与森林研究人员之间的合作与伙伴关系。为了更好地了解当前的做法，趋势，需求和机会，明尼苏达州已于1991、1996、2008和2017年投资收集了有关造林系统应用和森林管理活动的定量数据。基于这些数据，目标我们研究的目的是总结26年的数据，以表征和量化森林管理实践的趋势。在这段时间里，林地所有权（英亩）增加了，而采伐量却减少了（绳索）。跨州，联邦，县，森林工业和部落林地，这些林地共同代表明尼苏达州的大多数林地，清除系统从1991年的91％砍伐到2017年的72％。相比之下，从1991年到2017年，作为防护林，种子树，选育和间伐处理的一部分，总砍伐面积的比例翻了一番。影响变化的因素涉及森林健康和疾病，所有权结构的变化以及组织政策和/或目标的变化。所确定的因素反映了国家和国际其他地区森林管理者正在经历的许多趋势。所有权结构的变化，以及组织政策和/或目标的变化。所确定的因素反映了国家和国际其他地区森林管理者正在经历的许多趋势。所有权结构的变化，以及组织政策和/或目标的变化。所确定的因素反映了国家和国际其他地区森林管理者正在经历的许多趋势。