Rapid assessment surveys (RASs) of fouling and introduced seaweeds were conducted during late July, 2010 and early August, 2013 at multiple marina/harbor sites ranging from southern Maine to Rhode Island. Twenty sites were evaluated during 2010, and 19 in 2013 including 13 of the 2010 sites resurveyed. Based upon a composite of 19 study sites, 99 benthic algal taxa were recorded, including 24 Chlorophyceae, 23 Phaeophyceae, 45 Rhodophyceae, four macroscopic colonial diatoms (Bacillariophyceae), one Xanthophyceae, and two Cyanophyceae or Cyanobacteria. Twenty-seven species (27.3%) were limited to a single site, whereas only three taxa occurred at > 70% of the sites, including Ulva lactuca, Ceramium virgatum, and “Neosiphonia japonica.” Twelve introduced seaweeds were recorded, including one green, two brown, and nine red algae; their probable origins were the Australasia area, Europe, and the northwest and northeast Pacific. “Neosiphonia japonica,” which has recently been delineated within the NW Atlantic, was the most widely distributed adventive taxon, occurring at 100% of the combined nineteen sites, whereas Colpomenia peregrina and Melanosiphon intestinalis were only found at single sites (5.3%). A comparison of the species composition and distributional patterns of introduced seaweed taxa is made between the combined RASs of 2010 and 2013, and the findings of a similar RAS in southern England during 2005. The numbers of total taxa/site recorded at the 19 composite sites varied from 12–31 (mean = 22.0 ± 5.49 SD), with sites north of Cape Cod having slightly higher diversity patterns (i.e., 23.3 ± 5.2 SD) than those to the south (20.8 ± 5.6 SD). An assessment of Cheney's floristic ratios confirmed a wide range of cold- to warm-temperate taxa, as well as reduced numbers of brown algae at some sites, and an overall dominance of red algae. Several opportunistic and fast-growing native species (e.g., Ulva spp.) were also present in many of these highly disturbed habitats.

Erie Bluffs State Park in Erie County, Pennsylvania, established in 2004, occupies 219 ha along 2.25 km of Lake Erie shoreline. The park is notable for its highly erodible lakeshore bluffs, black oak sand barrens, and lakeplain swamp forests. A vascular plant inventory was undertaken and supplemented with historical collections to provide a vouchered checklist from the site now occupied by Erie Bluffs State Park. A second checklist with a list of unconfirmed records is based on unvouchered sightings from the park and specimen records from the vicinity of the park that cannot confidently be mapped within the park boundaries. The checklist includes 555 vascular taxa in 309 genera and 98 families with taxa representing the following groups: Equisetophyta (5), Lycopodiophyta (4), Pteridophyta (22), Coniferophyta (3), Liliopsida (136), and Magnoliopsida (385). Poaceae (56 species), Asteraceae (56 species), Cyperaceae (41 species), Rosaceae (36 species), and Brassicaceae (22 species) are the five largest families. The flora includes 391 species and subspecific taxa listed as native to Pennsylvania, and 159 that are introduced; the remaining five species are of uncertain native status. Twenty-three species are listed as species of concern, 19 represent Erie County records, and three are new to the flora of Pennsylvania. An additional 108 species are reported as unconfirmed records needing further inventory work. Plant communities are mapped and described. The vascular plant species of Erie Bluffs State Park are found among 14 natural communities and anthropogenic cover types, including 4 natural communities limited to the Great Lakes Region: Great Lakes Region Scarp Woodland; Great Lakes Bluff Seep; Elm–Ash–Maple Lakeplain Forest; and Black Oak Barrens.

Moser Park is a property in Allen County, Indiana, managed by New Haven Parks and Recreation. We conducted a plant survey within the forested section of the park, identifying and quantifying abundance of understory, midstory, and overstory plants. We calculated species richness and Shannon's index for all three strata and tested for relationships with environmental variables (i.e., canopy cover, soil compaction, litter depth, and light availability). The majority of understory species are typically associated with disturbed habitats, with very little resemblance to natural, pre-settlement habitat (i.e., low coefficient of conservation values). Understory cover was dominated by Rubus allegheniensis. Midstory stratum was less diverse than the understory and was dominated by an abundance of Fraxinus pennsylvanica, which was also an important species in the overstory. The forest at Moser Park matched the Hackberry–American Elm–Green Ash forest type. There was a lack of both Quercus and many Acer species within Moser Park that are common in the region. Because of the distinct soil types, and disturbance history, a relatively uncommon forest type for the region has developed in Moser Park that differs from the majority of forested land surrounding it.

Limestone is a distinctive substrate that has significant effects on soils and plants. The present study characterizes the diversity of vascular plants, bryophytes, and lichens at the Simonton Corner Quarry Preserve, an abandoned limestone quarry in Rockport, Maine, USA, which was in operation in the late 1800s. We document vascular plant diversity and associated edaphic features (i.e., soil pH and elemental chemistry) using 30 5×5 meter plots spread throughout the site. For vascular plants, 114 species in 96 genera and 50 families were observed; few of these species are known to prefer calcareous environments, and 38% are nonnative. Conversely, the soil- and rock-dwelling cryptogam biota, which comprises 21 moss species in 13 families and eight lichen species in three families, contains many calciphilic species. The bryoflora conspicuously lacks liverworts, whereas the lichen biota is dominated by cyanolichens. This study will inform future conservation and reclamation work at this and other human-altered limestone sites in Maine and floristically similar areas and contribute to our understanding of the geoecology of New England.