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Elevated population levels of white-tailed deer (Odocoileus virginianus Zimmerman) can drastically alter forest ecosystems and negatively impact society through human interactions such as deer vehicle collisions. It is currently difficult to estimate deer populations at multiple scales ranging from stand, county, state, and regional levels. This presents a challenge as natural resource managers develop silvicultural prescriptions and forest management practices aimed at successfully regenerating tree species in the face of deer browsing. This study utilized measurements of deer browse impact from the new tree regeneration indicator developed by the United States Department of Agriculture Forest Service Forest Inventory and Analysis (FIA) program. Seedling and sapling abundance and other plot-level characteristics were analyzed across three states (Michigan, Minnesota, and Wisconsin) in the Great Lakes Region of the United States. Socio-environmental datasets (Lyme disease cases, deer vehicle collisions, and deer density estimates) were used in conjunction with FIA data to determine their predictive power in estimating deer browse impacts by county. Predictions from random forests models indicate that using Lyme disease case reports, the number of deer-vehicle collisions, deer density estimates, and forest inventory information correctly predicted deer browse impact 70–90% of the time. Deer-vehicle collisions per county ranked highly important in the random forests for predicting deer browse impacts in all three states. Lyme disease cases ranked high in importance for the Lake States combined and for Minnesota and Wisconsin, separately. Results show the effectiveness of predicting deer browse impacts using a suite of freely available forest inventory and other socio-environmental information. [ABSTRACT FROM AUTHOR]

Abstract: We measure the extent and location of forest parcelization activity in a heavily forested Minnesota county between 1999 and 2006 and examine both the immediate and extended relationship between parcelization and development activity. We document forest land parcelization and development activity over time utilizing readily available real estate parcel data. Despite widespread perceptions of rapidly increasing rates of parcelization, we observed no significant positive or negative trend in parcelization activity in Itasca County during the study period: an average of only 0.4% of private forest land was parcelized each year. Parcelization was more common near cities, water, and public lands. While the overall rate of parcelization observed in this study may seem meager, closer examination of specific parcels suggest that parcelization is intimately tied to development activity and that this development occurs not long after parcelization. [Copyright &y& Elsevier]

We used radiotelemetry to examine foraging habitat preferences of 17 breeding, male northern goshawks (Accipiter gentilis) in Minnesota from 1998–2000. We assessed habitat preference using radio relocation points and 50-m radius buffers of radio relocation points. Our data suggested that foraging male goshawks used early-successional upland conifer stands (≥25 yrs old), early-successional upland deciduous stands (≥50 yrs old), late-successional upland conifer stands (≥50 yrs old), and late-successional upland deciduous stands (≥50 yrs old) more frequently than expected based on the abundance of these vegetation types in the landscape. The 2 most available stand types, early-successional upland deciduous (<25 yrs old) and all ages of late-successional lowland conifer stands, were used less than expected by foraging goshawks. Late-successional lowland deciduous stands (≥50 yrs old) were used in proportion to availability. Although analysis of relocation points suggested early-successional upland deciduous stands (25–49 yrs old) and late-successional upland conifer stands (≥50 yrs old) were used in proportion to availability, analysis of buffers around relocation points indicated that these stand types were also used more than expected by foraging goshawks. Regardless of vegetation community type, stands used by goshawks were structurally similar with high canopy and understory stem densities, high canopy closure, substantial shrub cover, and large amounts of woody debris. Nest stands consisted of taller and larger diameter canopy trees and fewer understory trees than foraging stands, but stands were otherwise similar in structural features, suggesting goshawks used similar stands for nesting and foraging but that they tended to select the most mature stands for nesting. A commonality among nesting and foraging stands was the presence of open spaces between the canopy and understory foliage, and between understory and shrub layer foliage. In our study area, these spaces may have served as relatively unobstructed flight paths where foraging and nesting stands possessed stem densities at the upper end of that reported for goshawk habitat. [ABSTRACT FROM AUTHOR]

We quantified standing stocks of large wood in 12 streams along the north shore of Lake Superior in northeastern Minnesota during June - September 2007. All large pieces of wood (>0.1 m in diameter for a portion > 1 m in length, n = 963) were measured. Standing stocks of large wood ranged from 0.01 to 0.48 pieces/m, lower than most published values from around the world. Wood inputs to streams in northeastern Minnesota may be less than elsewhere due to differences in tree species, environmental conditions, and past forest management practices. Regardless of wood input rates, the standing stocks of wood in northeastern Minnesota may have been reduced by intentional wood removal. [ABSTRACT FROM AUTHOR]

Old-growth forests are those that meet some threshold(s) determined by a scientific and political process. The main issue is what criteria to use to determine these thresholds; they must be practical enough to allow managers to delimit and manage old-growth stands in the field. People value forests with old and (or) big trees and primary forests that have a continuous heritage of natural disturbance and regeneration, even though the latter may include all stages of stand development and succession. We advocate uniting these two and using "primary forest", also called "natural heritage forest", as the criterion for delimiting old growth in regions where primary forest still exists. This criterion recognizes that the stage of development with big, old trees is part of a cycle of development, and it is necessary to have all the parts to continue to produce new examples of the older stages. The best available second-growth stands can be used in regions where primary forests are not available. Alternatively, threshold criteria for delimiting old growth can be based on tree size and age, but arbitrary criteria based on human size and age scales should be avoided in favour of criteria that specify stands dominated by trees relatively large and old for the species and site. Such criteria allow for old growth to occur across a variety of levels of site productivity, with trees of widely varying stature and with varying life-history characteristics, such as longevity, shade tolerance, and successional status. In any case, managers and scientists should work together to make sure that definitions work in the field but also include the ecological processes necessary to maintain the unique biological resources of old growth. The biological resources present in old growth may help to restore the second-growth landscape and allow reconstitution of forests in new places after global warming. Old-growth forests provide a baseline for comparison of effects of logging and natural disturbance, with respect to resilience to climatic change and disturbance, maintenance of species richness, and natural genetic structure of tree populations, which respond to different selective regimes in old growth and harvested forests. The species in old-growth remnants, their interactions and the resilience of the system after disturbance are as important or perhaps more so than the age and size of the trees at a given point in time. Key words: dwarf forest, Minnesota, old-growth processes, tree height.Les vieilles forêts sont celles qui rencontrent un ou des seuils déterminés par un processus scientifique ou politique. Le défi est de déterminer quels critères utiliser pour déterminer ces seuils; ils doivent être assez pratiques pour permettre aux aménagistes de délimiter et d'aménager les vieux peuplements sur le terrain. Le public valorise les forêts avec des arbres âgés ou de fortes dimensions, ainsi que les forêts primaires avec une histoire ininterrompue de perturbations naturelles et de régénérations. Nous proposons d'unir ces deux approches en utilisant le terme « forêt primaire » encore appelée « forêt patrimoniale naturelle », comme critère pour délimiter les vieilles forêts dans les régions où la forêt primaire existe toujours. Ce critère reconnaît que le stade de développement avec de gros arbres anciens constitue une partie du cycle de développement, et qu'il est nécessaire de disposer de toutes les parties du cycle pour continuer à produire de nouveaux exemples des stades les plus âgés. On peut utiliser les meilleures forêts de seconde venue, dans les régions où la forêt primaire n'existe plus. Comme alternative, les critères de seuil pour délimiter les vieilles forêts peuvent être basés sur la dimension et l'âge, mais les critères empiriques déterminés sur la base de dimension et d'âge à l'échelles humaines devraient être évités en faveurs de critères qui visent des peuplements dominés par des arbres relativement gros et âgés pour l'espèce et pour le site. De tels critères permettent de repérer des vieilles forêts pour un ensemble de niveaux de productivité des sites, avec des arbres de statures très variées, avec des caractéristiques variées de cycle de vie, tels que la longévité, la tolérance à l'ombre, et la place dans la succession. En toute éventualité, les aménagistes et les scientifiques devraient travailler ensemble pour s'assurer que les définitions sont utilisables sur le terrain, mais tiennent également compte du processus écologique nécessaire pour maintenir les ressources uniques de la vieille forêt. Les ressources biologiques présentes dans les vieilles forêts pourraient permettre de restaurer le paysage de seconde venue et de reconstituer des forêts en de nouveaux endroits, suite au réchauffement global. Les vieilles forêts fournissent une ligne de base pour comparer les effets à long terme de la récolte et des perturbations naturelles, en tenant compte de la résilience au changements de climat et de la perturbation, du maintient de la richesse en espèces, et de la richesse de la structure génétique des populations d'arbres, en réaction aux différents régimes sélectifs appliqués aux forêts âgées ou récoltées. Les espèces des vieilles forêts vestigiales, leurs interactions, et la résilience du système après perturbation sont aussi importantes, et peut-être plus importantes, que l'âge et la dimension des arbres, à un moment donné dans le temps. Mots clés : forêt naine, Minnesota, processus de vieillissement forestier, hauteur des arbres.[Traduit par la rédaction] [ABSTRACT FROM AUTHOR]