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Peri-urban natural areas, at the boundaries of cities and adjacent agricultural/ rural land, are subject to ecological threats endemic to both land use types. We used permanent plots to document changes in habitat quality by monitoring herbaceous-layer plant species presence and cover over a decade (1996/97 and 2007) in two peri-urban nature preserves in central Indiana, U.S.A. The preserves are comprised of different forest community types: wet-mesic depressional forest and mesic upland forest. Habitat characteristics, based on Floristic Quality Assessment parameters, showed only a single change for either preserve between survey years: wetness values were lower in the wet-mesic depressional site in 2007 than in 1996, indicating more plants with affinity for wet soil. No changes in community structure (total species richness, evenness, and diversity) were found. The number of nonnative species increased between survey years, especially in the wet-mesic depressional forest, where numbers went from zero to six, five of which are classified as invasive. There was considerable turnover in individual species presence, with perennial forb species the most likely species to be found in only 1 y or the other. Species did not rearrange themselves within plots, but completely appeared or disappeared from all plots within a preserve between the sample years, suggesting that species composition of the flora is dynamic. Management recommendations, including those related to evidence of heavy deer browse, are presented based on our findings. Repeat monitoring of our plots in future decades will allow quantification of any extinction debt that may now be in place due to the increased presence of nonnative species, especially invasive shrubs escaped from landscaping., INTRODUCTION The conversion of global land cover to urban use has increased by 58,000 [km.sup.2] from 19702000 with the largest change occurring in North America (Seto et al, 2011). This [...]

We examined the abundance and placement of leaf nests by fox squirrels in six urban woodlots in central Indiana ranging in size from 1.06 to 8.28 ha. Four of the woodlots were disturbed, or subject to extensive human impact, whereas the remaining two were nature preserves. We counted all leaf nests present in each woodlot and recorded nest tree characteristics. We then conducted a quantitative vegetation analysis of trees present and estimated percentages of herbaceous and shrub cover along a minimum of two 100 m transects at each site. Fox squirrels showed a preference to build nests in certain species of trees. However, preference for nest tree species was not consistent across sites. Fox squirrels preferred to build nests in large trees with vines in the canopy at all sites. Characteristics of nests and nest trees did not differ among sites, but nest density was greater in the disturbed sites compared to the nature preserve sites. The nature preserve sites differed from the disturbed sites only with regard to the amount of shrub and herbaceous cover; shrub cover was greater and herbaceous cover was less at the disturbed sites. Results of this study suggest that fox squirrels are flexible with regard to nest tree species used and that the choice of a nest tree is dependent, in part, on tree size and the presence of vines. Further, a higher density of leaf nests in disturbed woodlots suggests that habitat disturbance and fragmentation due to urbanization may not have detrimental effects on the abundance and persistence of fox squirrels.