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A biological inventory for multiple taxa aa 4,000 acre nature preserve.
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... For example, clearing for agriculture using fire resulted in a prevalence of red oak and white pine in the canopy of the mesic northern forest of Colonial Point on the northern shores of Burt Lake (Albert and Minc 1987). Several Great Lakes islands (e.g., Harbor Island and Garden Island) support red-oak-dominated mesic forests that likely originated following similar disturbance (Penskar et al. 2000, Penskar et al. 2001. Indigenous peoples indirectly influenced mesic ecosystems across the Great Lakes by maintaining low levels of white-tailed deer, which at high densities can drastically alter the structure and composition of mesic northern forest (detailed discussion below). ...
Widespread and sustained anthropogenic disturbance for the past 150 years has drastically altered mesic northern forest of the Great Lakes region. Human activity, primarily forest harvesting, has replaced small-scale windthrow as the primary force driving forest dynamics and landscape patterning. Mesic northern forests historically dominated vast areas of mesic uplands and were multi-generational, with old-growth conditions lasting many centuries. The overall extent of mesic northern forest, especially old-growth and late-successional forest, has severely declined with remnant patches becoming increasingly fragmented and even-aged. Remaining mesic forest has been subject to simplification of species composition and structural complexity. Hemlock and white pine, once common canopy associates, have become rare and localized, as have structural characteristics of old-growth forest, such as large diameter trees, coarse woody debris, and snags. High deer densities have contributed to the reduction of both floristic diversity and structural heterogeneity of these systems as deer browsing reduces herbaceous species richness and limits recruitment of seedlings and saplings, especially hemlock and white pine. Anthropogenic impacts to mesic northern forests have occurred at multiple scales, ranging from landscape fragmentation to genetic erosion. Restoration efforts to enhance the biodiversity values of mesic northern forest therefore require a multi-scale approach. Historical hindsight and ecological insight can help guide restoration. Knowledge of vegetative correlations to environmental parameters and historical context will assist resource managers in deciding where to focus their efforts. Total acreage of mesic northern forest can be increased by allowing early-successional stands to succeed to later-successional forest, while the effects of forest fragmentation can be dampened by reducing harvest and forest roads. Restoring structural, compositional, and functional characteristics of old-growth and late-successional mesic forest will require patience. Extending rotations in managed forests to over 100 years will allow for the development of late-successional characteristics. Where these traits persist, managers can maximize forest continuity by retaining large dead and living trees, especially mesic conifers. Hemlock and white pine restoration will be most successful when coordinated with regional efforts to reduce deer densities, promote the increase of conifer seed sources across the landscape, and restore old-growth and late-successional structure to mesic northern forest. Degradation of mesic northern forests has resulted from repeated and ubiquitous anthropogenic disturbance. Restoration of mesic northern forest will require sustained and widespread effort by resource managers across the Great Lakes region.
... Over the past two decades Michigan Natural Features Inventory (MNFI) has surveyed numerous natural communities and rare species found on or allied with Great Lakes islands. This extensive work was described in part by Soule (1993) and was detailed in previous years progress reports (Penskar et al. , and 2001 ). Conducting comprehensive biological inventories on Great Lakes islands is both timely and crucial to the conservation of biodiversity, as reflected in the findings and recommendations of The State of the Great Lakes Island Report (Vigmostad 1999). ...
... Information from recent surveys of the island was compiled and studied to delineate the areas of highest merit for inventory based on the relatively limited time allocated for fieldwork. Unlike island surveys conducted from 1998-2000 (Penskar et al. , 2001), our inventories were largely directed to interior sites, focusing on alvar (limestone pavement) and several rare plant species known to be associated with this globally rare natural community type. The principal species sought included prairie dropseed (Sporobolus heterolepis), flattened spike-rushPenskar et al. 2001, and Penskar et al. 1993), our high priority targets were Great Lakes endemic species such as dwarf lake iris (Iris lacustris), Houghtons goldenrod (Solidago houghtonii), Pitchers thistle (Cirsium pitcheri), and Michigan monkeyflower (Mimulus glabratus var. ...
... Unlike island surveys conducted from 1998-2000 (Penskar et al. , 2001), our inventories were largely directed to interior sites, focusing on alvar (limestone pavement) and several rare plant species known to be associated with this globally rare natural community type. The principal species sought included prairie dropseed (Sporobolus heterolepis), flattened spike-rushPenskar et al. 2001, and Penskar et al. 1993), our high priority targets were Great Lakes endemic species such as dwarf lake iris (Iris lacustris), Houghtons goldenrod (Solidago houghtonii), Pitchers thistle (Cirsium pitcheri), and Michigan monkeyflower (Mimulus glabratus var. michiganensis), all of which are federal and state listed. ...
