Ungulate browsing has been studied for several decades in the northern hemisphere. However, studies have mainly focused on just one or two ungulate species, while rarely contrasting the relative effects of summer and winter browsing. This limits our understanding of the dynamics and effects of browsing in landscapes where ungulate species diversity is increasing. We conducted a seasonal exclosure experiment on former clear-cuts in a multi-species ungulate system in Sweden, to investigate the relative impacts of summer and winter browsing on the conifers Scots pine (Pinus sylvestris) and Norway spruce (Picea abies) at the tree species level. We tested for differences in individual conifer growth and demographic responses between Summer browsing, Winter browsing, No browsing, and Control treatment plots over a 4.5 year experimental period. We defined the demographic response as the distribution of conifers among different height classes. Individual growth rates and demographic responses of both conifer species were similar in the plots with No browsing (year-round exclosures) as in the Control plots with year-round browsing. Plots subject to Summer and Winter browsing differed in terms of their demographic response relative to plots with No browsing and Control plots; more stems reached taller height classes in the Summer and Winter browsing plots with slight differences between the conifer species. We discuss the different responses of Scots pine and Norway spruce considering their differences in palatability and their ability to tolerate plant-plant competition in a multi-species ungulate system, in light of potential associational effects. If fencing is intended to be used as a management practice to mitigate the impacts of deer browsing on conifer growth, our results suggest that a total exclusion of deer does not necessarily enhance conifer growth during the first years of regeneration.

在北半球，数十年来一直研究无约束浏览。然而，研究主要集中在仅一种或两种有蹄类动物，而很少对比夏季和冬季浏览的相对影响。这限制了我们对有蹄类物种多样性在增加的景观中浏览动态和效果的理解。我们在瑞典的多物种有蹄类动物系统中对先前的无障碍区域进行了季节性暴露实验，以调查夏季和冬季浏览对树上的针叶树苏格兰松树（Pinus sylvestris）和挪威云杉（Picea abies）的相对影响物种级别。我们测试了夏季浏览之间各个针叶树生长和人口响应的差异，在4.5年的实验期内进行冬季浏览，不浏览和对照治疗。我们将人口响应定义为针叶树在不同高度类别之间的分布。在没有浏览的情况下，这两个针叶树种的个体生长率和人口统计学响应都相似（全年未暴露），与在全年浏览的情况下，对照地块相似。地块受夏季和冬季的浏览差异在他们的人口响应相对于与情节等方面没有浏览和控制地块; 夏季，更多的茎达到了更高的身高等级，冬季浏览图显示针叶树种之间存在细微差异。考虑到潜在的关联效应，考虑到它们在适口性上的差异以及它们在多物种有蹄类动物系统中耐受植物－植物竞争的能力，我们讨论了苏格兰松和挪威云杉的不同反应。如果打算将栅栏用作减轻鹿浏览对针叶树生长的影响的管理实践，那么我们的结果表明，完全排除鹿并不一定会在再生的头几年促进针叶树的生长。