Rhodora, which began publication in 1899, publishes work relating to the botany of North America and covers topics such as biogeography, conservation biology, ecology, evolution, floristics, paleobotany, population genetics and systematics.

Rhodora, which began publication in 1899, publishes work relating to the botany of North America and covers topics such as biogeography, conservation biology, ecology, evolution, floristics, paleobotany, population genetics and systematics.

In the course of its 125-year history, Rhodora has published seminal articles on cytogenetics, floristics, morphological taxonomy, and plant ecology. The journal has been a repository for taxonomic monographs, revisions, and treatments in addition to theoretical and applied nomenclatural adjustments, the latter sometimes in the framework of spirited debate. This article highlights the historical significance of some of these works.

This contribution is a study of the ecology of hybridization within the North American members of the Adiantum pedatum complex, a clade of maidenhair ferns; in the northeast part of its range, the clade comprises the diploids A. pedatum and A. aleuticum as well as their allotetraploid hybrid, A. viridimontanum. By utilizing fine-scale, field-collected data in concert with coarse-resolution climatic data, we characterized the realized ecological niche of the allotetraploid relative to its progenitors across habitat and range scales using a presence-only, envelope-based niche modeling approach. Our results demonstrate a pattern of niche intermediacy for A. viridimontanum across spatial scales and likewise at the habitat scale when the entire distribution of the three species in eastern North America is considered. However, the pattern of niche shift for the allotetraploid as characterized at the habitat scale is spatially variable; peripheral populations of the diploid species resolve in a portion of environmental space occupied only by the allotetraploid in the core portion of their range (where all three species co-occur). In geographic space, this pattern corresponds to the occupation of novel habitats by the allotetraploid in the core portion of its range, most notably serpentine mine barrens. These fine-scale results can be interpreted from the perspective of both niche conservatism and evolution, highlighting the importance of looking across spatial scales in studying ecological patterns.

The New England Botanical Club (Society as of February 27, 2021) has had 14 Editors-in-Chief since it started publishing Rhodora in 1899. All have had a strong connection to the organization and a passion for promoting the study of plants of North America, especially the flora of New England and adjacent areas. As a way of celebrating 125 years of publication, we profile the scientists who led the editorial team in maintaining a quality research publication. We include references to their scientific contributions in Rhodora and describe some of the many changes that have occurred in publishing and in botany during this time.

William G. Farlow was active in the founding of the New England Botanical Club in 1895. His influence extended to a group of local botanists, both amateur and professional, who were founding members of the Club and contributors to the early volumes of Rhodora. They collected across New England and published on bryophytes, algae, lichens, fungi, and vascular plants. Farlow was central to this activity, as were his collections and library. The Farlow Reference Library and Herbarium of Cryptogamic Botany recently celebrated the 100th anniversary of its founding. Farlow brought to his studies, and those researchers around him, approaches from his European training. A study of Farlow's work on the chestnut blight highlights the use of collections and the importance of documentation. The early works published in Rhodora by local cryptogamic botanists, and the documentation of their studies, have utility in today's investigations of distributional changes, habitat alterations, and invasion biology through the baseline studies that their work represents.

Erythronium americanum (trout lily) is a common spring ephemeral in the deciduous forests of the northeastern United States. Toward the end of its growing season in late spring, senescing corms produce a dropper (modified rhizome) to reposition one or more new corms within the soil profile. These droppers usually place the new corms deeper in the soil than the senescing corm, but occasionally and near hiking trails, the dropper goes aboveground. This study addressed the cause of this aboveground pattern. When corms were grown experimentally in compacted soil and drought conditions, only the compacted soil resulted in shallower droppers than the control. In a descriptive field study, aboveground droppers were significantly more common near trails where soil was more compacted than away from the trail. The results of this study suggest that soil compaction associated with hiking trails causes droppers to be shallower than away from the trail. This pattern may reduce survivorship and asexual reproduction in populations of E. americanum near hiking trails.

Desmids (sensu lato) are a group of morphologically diverse, freshwater algae, which have been used as biological indicators in some regions. In this study, we sampled three New England ponds from 2017 to 2019 and recorded their desmid floras. We then curated early- to mid-20th-century floristic data from the same ponds and compared them to our findings from 2017 to 2019 to document changes in desmid assemblages over the last 100 years. We assessed the past and current conservation value of the ponds using desmids as biological indicators. We documented a major decline in desmid diversity and conservation value of two of the ponds, but we documented remarkable diversity in Hawley Bog in western Massachusetts, with 66 taxa newly reported from the locality. Additionally, we documented the first record of Micrasterias brachyptera from New England. To aid future floristic efforts, we provided our species records and images in a public repository, the community-science database iNaturalist.