Carex secalina, a species native to eastern Europe and Asia, is reported as a new naturalized member of the North America flora. There are currently seven known populations in North America, all in southeastern New York State. In its native range, it is a species of damp or wet, often saline soils. In North America, it is known to grow predominately in highly disturbed urban habitats, including areas influenced by salt. It currently does not appear to be invasive in North America, but further monitoring is warranted due to its high potential fecundity. The updated Köppen-Geiger climate classification model is used to assess potential regions in North America where C. secalina might grow. Carex secalina is easily distinguished from all other members of the North American flora by a combination of the perigynia being very sharply two-angled and the spikes being pedunculate, especially proximally. Images of the species and its habitat in North America are presented, as are maps showing its distribution in its native and introduced ranges.

Triosteum aurantiacum subsp. aurantiacum is a rare plant associated with rich woods and thickets throughout eastern North America. Little is known about the ecology of this species, particularly in Nova Scotia, where it appears to be at the northern edge of its range, and occurs almost exclusively in river floodplains. This study presents a census of T. aurantiacum along three river valleys in Antigonish County, Nova Scotia, from which it was unreported prior to 2008: Pomquet River, West River, and South River. Plant height and number of shoots and fruits per genet were measured. Qualitative measurements were recorded of habitat and surrounding flora where plants were found. Soil pH and Ca contents were measured beside plants and at paired sites outside the floodplains to determine if soil preference could explain the observed plant distribution. Triosteum aurantiacum genets along Pomquet River were the tallest of the three riverside subpopulations, with the most fruiting plants. The West River subpopulation was the smallest and lacked stems < 40 cm tall, indicating poor recruitment at this site. Surprisingly, robust clusters of plants were also found at three upland locations along South River, well out of the floodplain. At all sites, the plants grew best in clearings and light shade in early successional forest, and were never found beneath closed canopy. Malus domestica, Prunus virginiana, Crataegus spp., and especially Fraxinus americana were common overstory trees. Soils were significantly less acid at sites supporting T. aurantiacum than at upland sites where the plant was absent, but there was no consistent difference in Ca concentrations. Impediments to long-distance dispersal or lack of suitable disturbed habitat may account for the absence of the plant from other river valleys in the area.

We documented changes in overstory species composition and foliar cover during a 23-year sampling period, compared woody species on three small islands in Lake Winnipesaukee, New Hampshire, and determined changes in dominant plant species over time. Floristic surveys had begun on these islands in 1901, and provided valuable information about earlier vascular plant composition. Three Mile Island, Hawk's Nest Island, and Blueberry Island were first sampled quantitatively in 1978, again in 1991, and most recently in 2001. The data compiled here are for woody vascular plant species found in long-term monitoring plots on the islands owned and/or managed by the Appalachian Mountain Club. Pinus resinosa, P. strobus, and Tsuga canadensis were the three most dominant species on Hawk's Nest throughout the study period. On Blueberry Island, Acer rubrum, Betula populifolia, and T. canadensis were the three most dominant woody species when sampling began. However, by 2001 Ilex verticillata, Myrica gale, and Vaccinium corymbosum were the three most dominant species. On Three Mile Island, P. strobus and Quercus rubra were the two most dominant species in 1978, but by 2001 A. pensylvanicum and Hamamelis virginiana were the dominants. Overall species richness within the permanent plots increased on Three Mile and Blueberry Islands, while the total number of species remained relatively constant on Hawk's Nest Island.