38 research outputs found

    EDGES AND RUSHES OF MINNESOTA: THE COMPLETEGUIDETOSPECIESIDENTIFICATION. Welby R. Smith; photography by Richard Haug.

    Get PDF
    Even the most seasoned individual with a plant identification background can relate to the difficulty of identifying sedges and rushes to the species level. Historically, one has had to rely on dichotomous keys to identify a sedge or rush species in the field. After hours of frustration, a person ends up collecting the plant and, if lucky, bringing the collection back to a herbarium where it can be compared to known specimens. I have been collecting and identifying sedge and rush species for over 25 years, and author Welby Smith along with photographer Richard Haug have published what I believe will be considered one of the most usable field guides for sedge and rush identification in the upper Midwest. I believe I should mention early in this review what makes this book such an amazing resource for field identification of sedges and rushes—the photography. The photography is of the highest quality I have ever seen! The array of photographs included with each species focuses on the characteristics that clearly differentiate one species from another. Each species usually has a photograph of the whole plant and sometimes the plant within its habitat. There are always photographs of the inflorescence and fruit, including perigynia or capsules and achenes or seeds. For example, the genus Carex includes photographs of the scale (sometimes the scale with the perigynium), the perigynium (usually dorsal and ventral views), and the achene, and in certain cases there are multiple photographs of each showing the changes in color during the season. Most of the photographs are of living plants and their parts, which is exactly what one would see in the field. Having pointed out this fact, it is mind-boggling how much time and effort that the people involved in the production of this book must have dedicated to putting this resource together. It had to be a passion or, at least, an obsession toward perfection

    Seed Production and Maturation of the Western Prairie Fringed Orchid

    Get PDF
    A population of threatened western prairie fringed orchid (Platanthera praeclara) was selected in 2004 on the Sheyenne National Grassland in southeastern North Dakota to study seed production and maturation for future use in population viability modeling. We randomly collected 30 seed capsules from the population under a permit from the U.S. Fish and Wildlife Service to: 1) identify capsule parameters that might be correlated with seed number and viability, 2) estimate an appropriate sample size to obtain accurate seed production estimates, 3) quantify seed production and viability per seed capsule, and 4) document temporal patterns in seed embryo development. We found that the number of seeds per capsule was weakly correlated with capsule weight (R2 = 0.23, P = 0.04), while the proportion of viable seeds within a capsule was weakly correlated with capsule length (R2 = 0.20, P = 0.01) and capsule circumference (R2 = 0.17, P = 0.04). However, seed production and embryo viability varied extensively in our study to the extent that capsule measurements were not reliable indicators of fecundity or fertility. Our study provides guidance for the sample size required to make statistical inferences regarding seed production and seed viability in western prairie fringed orchid populations. Our data also suggest that orchid seeds undergo maturation up to the time of capsule dehiscence based on increases we observed from August to September in seed weights and proportion of large embryos. Our observations reinforce the importance of moratoriums on grazing and mowing in some areas of orchid habitat until after mid-September

    Significant Surface-Water Connectivity of Geographically Isolated Wetlands

    Get PDF
    We evaluated the current literature, coupled with our collective research expertise, on surface-water connectivity of wetlands considered to be geographically isolated (sensu Tiner Wetlands 23:494–516, 2003a) to critically assess the scientific foundation of grouping wetlands based on the singular condition of being surrounded by uplands. The most recent research on wetlands considered to be geographically isolated shows the difficulties in grouping an ecological resource that does not reliably indicate lack of surface water connectivity in order to meet legal, regulatory, or scientific needs. Additionally, the practice of identifying geographically isolated wetlands based on distance from a stream can result in gross overestimates of the number of wetlands lacking ecologically important surface-water connections. Our findings do not support use of the overly simplistic label of geographically isolated wetlands . Wetlands surrounded by uplands vary in function and surface water connections based on wetland landscape setting, context, climate, and geographic region and should be evaluated as such. We found that the geographically isolated grouping does not reflect our understanding of the hydrologic variability of these wetlands and hence does not benefit conservation of the Nation’s diverse wetland resources. Therefore, we strongly discourage use of categorizations that provide overly simplistic views of surface water connectivity of wetlands fully embedded in upland landscapes

    Geographically Isolated Wetlands: Rethinking a Misnomer

    Get PDF
    Abstract We explore the category Bgeographically isolated wetlands^(GIWs; i.e., wetlands completely surrounded by uplands at the local scale) as used in the wetland sciences. As currently used, the GIW category (1) hampers scientific efforts by obscuring important hydrological and ecological differences among multiple wetland functional types, (2) aggregates wetlands in a manner not reflective of regulatory and management information needs, (3) implies wetlands so described are in some way Bisolated,^an often incorrect implication, (4) is inconsistent with more broadly used and accepted concepts of Bgeographic isolation,^and (5) has injected unnecessary confusion into scientific investigations and discussions. Instead, we suggest other wetland classification systems offer more informative alternatives. For example, hydrogeomorphic (HGM) classes based on wellestablished scientific definitions account for wetland functional diversity thereby facilitating explorations into questions of connectivity without an a priori designation of Bisolation.^Additionally, an HGM-type approach could be used in combination with terms reflective of current regulatory or policymaking needs. For those rare cases in which the condition of being surrounded by uplands is the relevant distinguishing characteristic, use of terminology that does not unnecessarily imply isolation (e.g., Bupland embedded wetlands^) would help alleviate much confusion caused by the Bgeographically isolated wetlands^misnomer

    Typha (Cattail) Invasion in North American Wetlands: Biology, Regional Problems, Impacts, Ecosystem Services, and Management

    Get PDF
    Typha is an iconic wetland plant found worldwide. Hybridization and anthropogenic disturbances have resulted in large increases in Typha abundance in wetland ecosystems throughout North America at a cost to native floral and faunal biodiversity. As demonstrated by three regional case studies, Typha is capable of rapidly colonizing habitats and forming monodominant vegetation stands due to traits such as robust size, rapid growth rate, and rhizomatic expansion. Increased nutrient inputs into wetlands and altered hydrologic regimes are among the principal anthropogenic drivers of Typha invasion. Typha is associated with a wide range of negative ecological impacts to wetland and agricultural systems, but also is linked with a variety of ecosystem services such as bioremediation and provisioning of biomass, as well as an assortment of traditional cultural uses. Numerous physical, chemical, and hydrologic control methods are used to manage invasive Typha, but results are inconsistent and multiple methods and repeated treatments often are required. While this review focuses on invasive Typha in North America, the literature cited comes from research on Typha and other invasive species from around the world. As such, many of the underlying concepts in this review are relevant to invasive species in other wetland ecosystems worldwide

    EDGES AND RUSHES OF MINNESOTA: THE COMPLETEGUIDETOSPECIESIDENTIFICATION. Welby R. Smith; photography by Richard Haug.

    Get PDF
    Even the most seasoned individual with a plant identification background can relate to the difficulty of identifying sedges and rushes to the species level. Historically, one has had to rely on dichotomous keys to identify a sedge or rush species in the field. After hours of frustration, a person ends up collecting the plant and, if lucky, bringing the collection back to a herbarium where it can be compared to known specimens. I have been collecting and identifying sedge and rush species for over 25 years, and author Welby Smith along with photographer Richard Haug have published what I believe will be considered one of the most usable field guides for sedge and rush identification in the upper Midwest. I believe I should mention early in this review what makes this book such an amazing resource for field identification of sedges and rushes—the photography. The photography is of the highest quality I have ever seen! The array of photographs included with each species focuses on the characteristics that clearly differentiate one species from another. Each species usually has a photograph of the whole plant and sometimes the plant within its habitat. There are always photographs of the inflorescence and fruit, including perigynia or capsules and achenes or seeds. For example, the genus Carex includes photographs of the scale (sometimes the scale with the perigynium), the perigynium (usually dorsal and ventral views), and the achene, and in certain cases there are multiple photographs of each showing the changes in color during the season. Most of the photographs are of living plants and their parts, which is exactly what one would see in the field. Having pointed out this fact, it is mind-boggling how much time and effort that the people involved in the production of this book must have dedicated to putting this resource together. It had to be a passion or, at least, an obsession toward perfection

    Cattle Grazing Reduces Survival and Reproduction of the Western Prairie Fringed Orchid

    Get PDF
    QuantifYing impacts of livestock grazing and prairie management strategies on the threatened western prairie\u27 fringed orchid (Platanthera praeclara) is difficult due to the erratic appearance of the orchid above-ground. We monitored above-ground survival of orchids from flowering to mature seed capsule production, comparing plant height, flower numbers, and seed capsule numbers from 2002-2004 in rotationally grazed pastures and non-grazed sites. Orchid survival differed significantly between grazed and non-grazed pastures, with the proportion of plants surviving from flower to capsule production consistently lower in grazed pastures. Mean orchid survival in grazed and non-grazed areas was 40% and 87%, respectively. The proportion., of surviving plants producing capsules greater than 3 mm in diameter was significantly greater in non-grazed pastures. Flower and bud production did not differ between grazed and non-grazed areas, tlnd plant height was significantly greater in non-grazed) areas. High levels of above-ground plant mortality may reduce orchid tuber winter survival and robustness of above-ground; growth the following growing season. Creation of protected orchid nursery areas within grazed pastures is suggested to reduce high mortality of above-ground orchid plants

    Seed Production and Maturation of the Western Prairie Fringed Orchid

    Get PDF
    A population of threatened western prairie fringed orchid (Platanthera praeclara) was selected in 2004 on the Sheyenne National Grassland in southeastern North Dakota to study seed production and maturation for future use in population viability modeling. We randomly collected 30 seed capsules from the population under a permit from the U.S. Fish and Wildlife Service to: 1) identify capsule parameters that might be correlated with seed number and viability, 2) estimate an appropriate sample size to obtain accurate seed production estimates, 3) quantify seed production and viability per seed capsule, and 4) document temporal patterns in seed embryo development. We found that the number of seeds per capsule was weakly correlated with capsule weight (R2 = 0.23, P = 0.04), while the proportion of viable seeds within a capsule was weakly correlated with capsule length (R2 = 0.20, P = 0.01) and capsule circumference (R2 = 0.17, P = 0.04). However, seed production and embryo viability varied extensively in our study to the extent that capsule measurements were not reliable indicators of fecundity or fertility. Our study provides guidance for the sample size required to make statistical inferences regarding seed production and seed viability in western prairie fringed orchid populations. Our data also suggest that orchid seeds undergo maturation up to the time of capsule dehiscence based on increases we observed from August to September in seed weights and proportion of large embryos. Our observations reinforce the importance of moratoriums on grazing and mowing in some areas of orchid habitat until after mid-September

    In Situ Development of Western Prairie Fringed Orchid Seeds, Protocorms, and Seedlings in Grazed and Non-Grazed Prairie Habitat

    Get PDF
    In 1989, the U.S. Fish and Wildlife Service listed the western prairie fringed orchid (Platanthera praeclara) as threatened. Although this orchid has been monitored for years, there is little scientific documentation of its biology, ecology, and phenology, nor the impacts of management activities on its populations. Our objectives were to document seed germination and seedling production rates after one year in situ, and compare seed germination in grazed and non-grazed prairie habitat in the Sheyenne National Grassland (SNG) in southeastern North Dakota. Of 18,717 planted seeds, we recovered 1,561 swollen embryos, 94 protocorms, and 51 seedlings. We documented no difference in germination rate between seeds planted in grazed versus non-grazed prairie. However, our results suggested that 15 new flowering orchids may be produced from each flowering orchid that survives the growing season on the SNG. Thus, our findings confirm successful production of western prairie fringed orchid seedlings after one year in situ. Further research is needed to evaluate potential impacts of livestock grazing on other stages of the orchid life cycle, particularly protocorm and seedling survival rates

    Impacts and Drivers of Smooth Brome (<i>Bromus inermis</i> Leyss.) Invasion in Native Ecosystems

    No full text
    Smooth brome (Bromus inermis Leyss.) is an invasive cool-season grass that has spread throughout the Great Plains of North America. The species is considered one of the most widespread exotic grasses that has successfully invaded both cool-season and warm-season native prairies. In the prairies where it has invaded, there has often been a total elimination of native species and an overall homogenization of ecosystems. Smooth brome has greater competitive abilities compared to many native grasses and can foster their total elimination in many instances. The greater competitiveness can be partially attributed to its ability to alter the soil and hydrological properties of a site. It is a deep-rooted rhizomatous grass species that thrives in nitrogen-enriched soil, and since its leaf tissue decomposes faster than native species, it in turn increases the soil nitrogen level, causing positive plant-soil feedback. Moreover, smooth brome is able to transport the required nutrients from older plants to the newer progenies invading new nutrient-depleted areas, making it a potent invader. However, the impact of smooth brome is not limited to soil biochemistry alone; it also affects other ecosystem components such as the movement and behavior of many native arthropods, thereby altering the overall population dynamics of such species. Thus, smooth brome invasion poses a serious threat to the remnant prairies of the Great Plains, and efficient management strategies are urgently needed to control its invasion. Control measures such as mowing, grazing, burning, and herbicide application have been effectively used to manage this species. However, due to the widespread distribution of smooth brome across North America and its adaptability to a wide range of environmental conditions, it is challenging to translate the management strategies from one area to another
    corecore