{"title":"Updating the Vascular Flora of Windham County, Connecticut","authors":"L. Standley, B. Connolly","doi":"10.3119/21-01","DOIUrl":"https://doi.org/10.3119/21-01","url":null,"abstract":"","PeriodicalId":54454,"journal":{"name":"Rhodora","volume":null,"pages":null},"PeriodicalIF":0.2,"publicationDate":"2022-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47157590","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"New Records of the Woody Introduced Species Aralia elata (Apiaceae) and Symplocos paniculata in Massachusetts","authors":"L. Standley","doi":"10.3119/21-02","DOIUrl":"https://doi.org/10.3119/21-02","url":null,"abstract":"","PeriodicalId":54454,"journal":{"name":"Rhodora","volume":null,"pages":null},"PeriodicalIF":0.2,"publicationDate":"2022-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45469363","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Gregory D. Turner, Kelly Ryan, William A Ricci, Kendra McMillin, G. Hertel
ABSTRACT. Urban forests of northeastern North America are often seen as degraded ecosystems with little ecological diversity or value. This is especially true given that native tree species declines in these forests have resulted from low recruitment caused by abundant exotic species, mortality from pathogens and pests, and severe deer browse. This study assessed tree composition and size structure of species found at the Robert B. Gordon Natural Area for Environmental Studies, an urban 51 ha forest fragment located 36 km west of Philadelphia, Pennsylvania. The study quantified and compared tree species from 15 plots located in mid- to late-successional forest stands. Species were categorized as native or exotic and resistant or nonresistant to deer browse. We quantified tree densities per species and measured diameter at breast height of all individuals > 2.5 cm and used this information to quantify relative importance values and assign trees to size classes. Natives Liriodendron tulipifera and Fagus grandifolia, and exotic Acer platanoides, dominated composition (i.e., 45.3% of total relative importance), with L. tulipifera most dominant. Natives had significantly greater densities than exotics in all size classes that included both categories, except for a 10–20 cm class, regardless of whether F. grandifolia, a prolific root sprouter, was included or excluded from comparisons. When F. grandifolia was excluded, nonresistant species had significantly greater densities than resistant ones in classes ranging from the smallest to larger classes. The prominence of nonresistant species in the smallest classes was unexpected given intense deer browsing.
摘要北美东北部的城市森林通常被视为退化的生态系统，几乎没有生态多样性或价值。考虑到这些森林中本地树种的减少是由于大量外来物种导致的补充不足、病原体和害虫的死亡以及鹿的严重啃食造成的，这一点尤其正确。这项研究评估了Robert B. Gordon自然环境研究区发现的树木组成和物种大小结构，这是一个位于宾夕法尼亚州费城以西36公里的51公顷的城市森林碎片。本研究对位于中后期演替林分的15个样地的树种进行了量化比较。物种分为本地和外来以及对鹿食有抗性和无抗性。我们量化了每个树种的树密度，并测量了所有个体在胸高为2.5 cm时的直径，并利用这些信息量化了相对重要性值，并将树木划分为大小类别。本土鹅毛楸、大叶Fagus和外来平叶槭(Acer platanoides)以鹅毛楸(L. tulipifera)为优势，相对重要性占45.3%。除了10-20 cm级外，在包括这两个类别的所有大小类别中，土生植物的密度都显著高于外来植物，无论是否包括或不包括多产的根发芽植物桔梗(F. grandfolia)。在排除桔梗的情况下，从最小纲到较大纲，非抗性种的密度均显著高于抗性种。考虑到鹿的强烈食食，非抗性物种在最小类中的突出是出乎意料的。
{"title":"Tree Composition and Size Structure Based on Nativity and Deer Resistance at an Urban Forest in Southeast Pennsylvania","authors":"Gregory D. Turner, Kelly Ryan, William A Ricci, Kendra McMillin, G. Hertel","doi":"10.3119/20-11","DOIUrl":"https://doi.org/10.3119/20-11","url":null,"abstract":"ABSTRACT. Urban forests of northeastern North America are often seen as degraded ecosystems with little ecological diversity or value. This is especially true given that native tree species declines in these forests have resulted from low recruitment caused by abundant exotic species, mortality from pathogens and pests, and severe deer browse. This study assessed tree composition and size structure of species found at the Robert B. Gordon Natural Area for Environmental Studies, an urban 51 ha forest fragment located 36 km west of Philadelphia, Pennsylvania. The study quantified and compared tree species from 15 plots located in mid- to late-successional forest stands. Species were categorized as native or exotic and resistant or nonresistant to deer browse. We quantified tree densities per species and measured diameter at breast height of all individuals > 2.5 cm and used this information to quantify relative importance values and assign trees to size classes. Natives Liriodendron tulipifera and Fagus grandifolia, and exotic Acer platanoides, dominated composition (i.e., 45.3% of total relative importance), with L. tulipifera most dominant. Natives had significantly greater densities than exotics in all size classes that included both categories, except for a 10–20 cm class, regardless of whether F. grandifolia, a prolific root sprouter, was included or excluded from comparisons. When F. grandifolia was excluded, nonresistant species had significantly greater densities than resistant ones in classes ranging from the smallest to larger classes. The prominence of nonresistant species in the smallest classes was unexpected given intense deer browsing.","PeriodicalId":54454,"journal":{"name":"Rhodora","volume":null,"pages":null},"PeriodicalIF":0.2,"publicationDate":"2022-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45496705","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In May 2020, in connection with a project to familiarize myself with the nonnative dandelions (Taraxacum F. H. Wigg.) in the flora of Vermont, I encountered a population of a very distinctive dandelion in a meadow in Hardwick, Caledonia County. Upon study with relevant literature and illustrations (Dudman and Richards 1997; Richards 2012; Richards and Sell 1976; Stace 2019; Trávníček and Vašut 2011), I determined it to be T. hamatum Raunk. (Figure 1). Voucher specimens were collected and are deposited at MT, NEBC, and VT. Taraxacum hamatum Raunk., Dansk Exskurs.-Fl., ed. 2: 225 (1906) was based on a type from Denmark: Sjaelland (Zealand), Jonstrup Væng, skoveng [forest], 14 May 1905, Raunkier s.n., lectotype at C (C10021066), chosen by Øllgaard, not seen. An image of the lectotype specimen was published by Øllgaard (1983); an image of a duplicate (S10-38037) is available on JSTOR Global Plants (2020). Excellent illustrations may be found in Dudman and Richards (1997), Richards (2012), and Trávníček and Vašut (2011). Relevant characters for identification, to which this collection fully conforms, include the following:
{"title":"Hook-Lobed Dandelion, Taraxacum hamatum (T. Section Hamata: Asteraceae) in Vermont","authors":"Arthur V. Gilman","doi":"10.3119/20-31","DOIUrl":"https://doi.org/10.3119/20-31","url":null,"abstract":"In May 2020, in connection with a project to familiarize myself with the nonnative dandelions (Taraxacum F. H. Wigg.) in the flora of Vermont, I encountered a population of a very distinctive dandelion in a meadow in Hardwick, Caledonia County. Upon study with relevant literature and illustrations (Dudman and Richards 1997; Richards 2012; Richards and Sell 1976; Stace 2019; Trávníček and Vašut 2011), I determined it to be T. hamatum Raunk. (Figure 1). Voucher specimens were collected and are deposited at MT, NEBC, and VT. Taraxacum hamatum Raunk., Dansk Exskurs.-Fl., ed. 2: 225 (1906) was based on a type from Denmark: Sjaelland (Zealand), Jonstrup Væng, skoveng [forest], 14 May 1905, Raunkier s.n., lectotype at C (C10021066), chosen by Øllgaard, not seen. An image of the lectotype specimen was published by Øllgaard (1983); an image of a duplicate (S10-38037) is available on JSTOR Global Plants (2020). Excellent illustrations may be found in Dudman and Richards (1997), Richards (2012), and Trávníček and Vašut (2011). Relevant characters for identification, to which this collection fully conforms, include the following:","PeriodicalId":54454,"journal":{"name":"Rhodora","volume":null,"pages":null},"PeriodicalIF":0.2,"publicationDate":"2022-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43610622","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kevin Berend, K. Amatangelo, D. Weihrauch, C. Norment, M. Penberthy
ABSTRACT. In northeastern North America, alpine snowbank communities are rare plant assemblages that form in sheltered sites above treeline where late-lying snow provides insulation from late-season frosts and a longer-lasting source of water. We measured snowpack and studied community composition and plant traits at the species and community scales across the snowmelt gradient at snowbank sites on Mt. Washington, New Hampshire. We used nonmetric multidimensional scaling ordination and analysis of similarity to examine community composition across the snowmelt gradient and measured plant traits (height, leaf dry matter content, leaf area, and specific leaf area) of four focal species (Carex bigelowii, Chamaepericlymenum canadense, Clintonia borealis, and Maianthemum canadense). We assessed trait variability of the four focal species across the snowmelt gradient and evaluated community-weighted mean trait values and phenotypic plasticity between snowbank core and edge habitats. Analysis of similarity indicated that vascular plant diversity increased (p < 0.001), lichen and bryophyte cover decreased (p < 0.001; p < 0.025), and community-weighted mean leaf area increased (p < 0.001) in the core of snowbank communities where melting dates were later. Analysis of similarity indicated that vascular plant communities varied significantly across the snowmelt gradient. The transition in community composition and trait values across the snowmelt gradient are indicative of changing environmental conditions and ecosystem functions, though more research is needed to determine the extent to which phenotypic plasticity and ecotypic uniqueness influence trait expression of snowbank species. Genetic analysis may be necessary to evaluate population dynamics among isolated alpine communities, which may be vulnerable to climate change or displacement by exotic or lowland species.
{"title":"Plant Traits and Community Metrics across a Snowmelt Gradient at Alpine Snowbank Sites on Mt. Washington, New Hampshire","authors":"Kevin Berend, K. Amatangelo, D. Weihrauch, C. Norment, M. Penberthy","doi":"10.3119/20-14","DOIUrl":"https://doi.org/10.3119/20-14","url":null,"abstract":"ABSTRACT. In northeastern North America, alpine snowbank communities are rare plant assemblages that form in sheltered sites above treeline where late-lying snow provides insulation from late-season frosts and a longer-lasting source of water. We measured snowpack and studied community composition and plant traits at the species and community scales across the snowmelt gradient at snowbank sites on Mt. Washington, New Hampshire. We used nonmetric multidimensional scaling ordination and analysis of similarity to examine community composition across the snowmelt gradient and measured plant traits (height, leaf dry matter content, leaf area, and specific leaf area) of four focal species (Carex bigelowii, Chamaepericlymenum canadense, Clintonia borealis, and Maianthemum canadense). We assessed trait variability of the four focal species across the snowmelt gradient and evaluated community-weighted mean trait values and phenotypic plasticity between snowbank core and edge habitats. Analysis of similarity indicated that vascular plant diversity increased (p < 0.001), lichen and bryophyte cover decreased (p < 0.001; p < 0.025), and community-weighted mean leaf area increased (p < 0.001) in the core of snowbank communities where melting dates were later. Analysis of similarity indicated that vascular plant communities varied significantly across the snowmelt gradient. The transition in community composition and trait values across the snowmelt gradient are indicative of changing environmental conditions and ecosystem functions, though more research is needed to determine the extent to which phenotypic plasticity and ecotypic uniqueness influence trait expression of snowbank species. Genetic analysis may be necessary to evaluate population dynamics among isolated alpine communities, which may be vulnerable to climate change or displacement by exotic or lowland species.","PeriodicalId":54454,"journal":{"name":"Rhodora","volume":null,"pages":null},"PeriodicalIF":0.2,"publicationDate":"2022-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42228095","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-04-12DOI: 10.3119/0035-4902-122.992.361
{"title":"Reviewers of Manuscripts 2019–2020","authors":"","doi":"10.3119/0035-4902-122.992.361","DOIUrl":"https://doi.org/10.3119/0035-4902-122.992.361","url":null,"abstract":"","PeriodicalId":54454,"journal":{"name":"Rhodora","volume":null,"pages":null},"PeriodicalIF":0.2,"publicationDate":"2022-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42154827","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Inside Front Cover","authors":"","doi":"10.1039/d1re90013g","DOIUrl":"https://doi.org/10.1039/d1re90013g","url":null,"abstract":"","PeriodicalId":54454,"journal":{"name":"Rhodora","volume":null,"pages":null},"PeriodicalIF":0.2,"publicationDate":"2021-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1039/d1re90013g","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44987596","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-08-20DOI: 10.3119/0035-4902-122.991.239
{"title":"Junior Faculty Award on the Flora of New England","authors":"","doi":"10.3119/0035-4902-122.991.239","DOIUrl":"https://doi.org/10.3119/0035-4902-122.991.239","url":null,"abstract":"","PeriodicalId":54454,"journal":{"name":"Rhodora","volume":null,"pages":null},"PeriodicalIF":0.2,"publicationDate":"2021-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47080496","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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