Download or read book North American Species of Agrostis written by Albert Spear Hitchcock and published by . This book was released on 1905 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book North American Species of Agrostis written by United States. Department of Agriculture and published by . This book was released on 1904 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book North American Species of Agrostis written by Albert S. Hitchcock and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book North American Species of Agrostis Classic Reprint written by Albert Spear Hitchcock and published by Forgotten Books. This book was released on 2017-11-19 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: Excerpt from North American Species of Agrostis The present paper is an attempt to classify our knowledge concern ing one of our most perplexing genera of grasses. It deals chiefly with those species found north of Mexico, but includes a few notes on the Mexican species. The preparatory study naturally divided itself into two rather distinct lines - the classification of the species, or taxonomy, and the history of the Species, or nomenclature. Each line presents difficulties, a few of which are discussed below. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.
Download or read book A Sectional Treatment for the North American Species of Agrostis written by Alan Ackerman Beetle and published by . This book was released on 1950 with total page 35 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book North American Species of Agrostis by A S Hitchcock written by Albert Spear Hitchcock and published by . This book was released on 1905 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NORTH AMER SPECIES OF AGROSTIS written by A. S. (Albert Spear) 1865-19 Hitchcock and published by . This book was released on 2016-08-29 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book North American species of Agrostis written by Albert Spear Hitchcock and published by . This book was released on 1905 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Biosystematic Study of Some North American Species of Agrostis L and Podagrostis Griseb Scribn Merr written by Curt Gerald Carlbom and published by . This book was released on 1967 with total page 446 pages. Available in PDF, EPUB and Kindle. Book excerpt: A taxonomic investigation was made of 24 taxa belonging to the section Trichodium (Michx.) Trin., of Agrostis, and the genus Podagrostis. Experimental methods were employed, including: uniform garden culture of transplants and plants grown from seeds collected in natural populations; breeding studies; physiological and phenological investigations; cytological studies; ecological studies in natural populations. Herbarium exsiccatae including the type material of most of the 24 taxa were studied. In addition, comparative morphological studies were made of several of the taxa in their natural habitats and again in the uniform experimental garden. Twenty-four taxa are recognized in this study. Generic and species descriptions, distributional maps, generic and species keys, photographs of 23 taxa including several types, and photomicrographs of meiotic and mitotic figures of 12 taxa are presented. In addition, the various taxa are discussed individually, and the criteria and concepts used for species delimitation in Agrostis and Podagrostis are presented. Chromosome counts of nine species and two varieties of Agrostis and three species of Podagrostis are reported for the first time. Additional counts of other native taxa confirm earlier published counts. Eleven of the 19 species of Agrostis are hexaploids, four species are known to be tetraploids and two species are octoploids. Two hexaploid groups have been delimited - the A. exarata and A. dieqoensis complexes. The three Podagrostis species, P. aequivalvis, P. humilis and P. thurberiana are diploids, 2n = 14. This chromosome number supports previous morphological evidence that Podagrostis is an independent evolutionary group deserving generic status. Three Old World species of Agrostis, adventive in western North America, have been studied cytologically, and chromosome counts are presented. Agrostis perennans, hitherto unknown in western North America, was collected by the investigator on the Olympic Peninsula of Washington. Putative natural hybridization and introgression were observed between several taxa of Agrostis and Podagrostis, namely: A. diegoensis and A. hallii; A. diegoensis and A. pallens; P. humilis and P. thureriana. Physiological races in P. thurberiana and A. exarata have been studied. Clinal races occur with a north-south distributional pattern in P. thurberiana. Races from southern California flowered under shorter photoperiods, while races from northern California, Oregon and Washington flowered at successively later dates under increased photoperiodic regimes. Mountain ecotypes of A. exarata were obligately long-day plants, while sea-level ecotypes were day-neutral and remontant. Agrostis howellii, a species found near sea level, required a long-day photo-periodic regime and cold vernalization for floral initiation. Autogamy occurs in several of the native species of Agrostis. Facultative autogamy seems to occasion rapid ecotypic and racial diversification with concomitant morphological complexity within the taxa. A tentative phylogenetic scheme is presented. The North American species of Agrostis are believed to comprise two main evolutionary groups; the "primitive" and "derived" species of section Trichodium. The "primitive" taxa are chiefly characterized by: 1) having some species with Old World distributions; 2) more northern and/or widespread distributions; 3) a perennial habit; 4) mostly medium to large anthers; 5) reproducing by allogamy; 6) having tetra-, hexa-, and octoploid chromosome levels; 7) inhabiting mesic and sylvan or bog habitats; 8) occurring on older geological formations and soils. The "derived" species are characterized by: 1) not having any conspecific taxa in the Old World; 2) more southern distributions; 3) being weakly perennial or annual; 4) small anthers; 5) reproducing by autogamy or facultative auto-gamy; 6) having hexa- and octoploid chromosome levels; 7) occupying arid and semi-arid habitats; 8) occurring on newer geological formations and soils.
Download or read book A Biosystematic Study of Some North American Species of Agrostis L and Podagrostis Griseb Scribn Merr written by Curt Gerald Carlbom and published by . This book was released on 1967 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: A taxonomic investigation was made of 24 taxa belonging to the section Trichodium (Michx.) Trin., of Agrostis, and the genus Podagrostis. Experimental methods were employed, including: uniform garden culture of transplants and plants grown from seeds collected in natural populations; breeding studies; physiological and phenological investigations; cytological studies; ecological studies in natural populations. Herbarium exsiccatae including the type material of most of the 24 taxa were studied. In addition, comparative morphological studies were made of several of the taxa in their natural habitats and again in the uniform experimental garden. Twenty-four taxa are recognized in this study. Generic and species descriptions, distributional maps, generic and species keys, photographs of 23 taxa including several types, and photomicrographs of meiotic and mitotic figures of 12 taxa are presented. In addition, the various taxa are discussed individually, and the criteria and concepts used for species delimitation in Agrostis and Podagrostis are presented. Chromosome counts of nine species and two varieties of Agrostis and three species of Podagrostis are reported for the first time. Additional counts of other native taxa confirm earlier published counts. Eleven of the 19 species of Agrostis are hexaploids, four species are known to be tetraploids and two species are octoploids. Two hexaploid groups have been delimited - the A. exarata and A. dieqoensis complexes. The three Podagrostis species, P. aequivalvis, P. humilis and P. thurberiana are diploids, 2n = 14. This chromosome number supports previous morphological evidence that Podagrostis is an independent evolutionary group deserving generic status. Three Old World species of Agrostis, adventive in western North America, have been studied cytologically, and chromosome counts are presented. Agrostis perennans, hitherto unknown in western North America, was collected by the investigator on the Olympic Peninsula of Washington. Putative natural hybridization and introgression were observed between several taxa of Agrostis and Podagrostis, namely: A. diegoensis and A. hallii; A. diegoensis and A. pallens; P. humilis and P. thureriana. Physiological races in P. thurberiana and A. exarata have been studied. Clinal races occur with a north-south distributional pattern in P. thurberiana. Races from southern California flowered under shorter photoperiods, while races from northern California, Oregon and Washington flowered at successively later dates under increased photoperiodic regimes. Mountain ecotypes of A. exarata were obligately long-day plants, while sea-level ecotypes were day-neutral and remontant. Agrostis howellii, a species found near sea level, required a long-day photo-periodic regime and cold vernalization for floral initiation. Autogamy occurs in several of the native species of Agrostis. Facultative autogamy seems to occasion rapid ecotypic and racial diversification with concomitant morphological complexity within the taxa. A tentative phylogenetic scheme is presented. The North American species of Agrostis are believed to comprise two main evolutionary groups; the "primitive" and "derived" species of section Trichodium. The "primitive" taxa are chiefly characterized by: 1) having some species with Old World distributions; 2) more northern and/or widespread distributions; 3) a perennial habit; 4) mostly medium to large anthers; 5) reproducing by allogamy; 6) having tetra-, hexa-, and octoploid chromosome levels; 7) inhabiting mesic and sylvan or bog habitats; 8) occurring on older geological formations and soils. The "derived" species are characterized by: 1) not having any conspecific taxa in the Old World; 2) more southern distributions; 3) being weakly perennial or annual; 4) small anthers; 5) reproducing by autogamy or facultative auto-gamy; 6) having hexa- and octoploid chromosome levels; 7) occupying arid and semi-arid habitats; 8) occurring on newer geological formations and soils
Download or read book The North American Species of Panicum written by Albert Spear Hitchcock and published by . This book was released on 1910 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The North American Species of Pennisetum written by Agnes Chase and published by . This book was released on 1920 with total page 938 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Flora of North America North of Mexico written by Flora of North America Editorial Committee and published by . This book was released on 1993 with total page 941 pages. Available in PDF, EPUB and Kindle. Book excerpt: FNA presents for the first time, in one published reference source, information on the names, taxonomic relationships, continent-wide distributions, and morphological characteristics of all plants native and naturalized found in North America north of Mexico.
Download or read book Manual of Grasses for North America written by Mary E. Barkworth and published by University Press of Colorado. This book was released on 2007-09-15 with total page 1552 pages. Available in PDF, EPUB and Kindle. Book excerpt: Grasses are the world’s most important plants. They are the dominant species over large parts of the earth’s land surface, a fact that is reflected in the many different words that exist for grasslands, words such as prairie, veldt, palouse, and pampas to mention just a few. As a group, grasses are of major ecological importance, as soil binders and providers of shelter and food for wild animals, both large and small. Some grasses, such as wheat, rice, corn, barley, rye, tef, and sugar cane are major sources of calories for humans and their livestock; others, primarily bamboos, are used for construction, tools, paper, and fabric. More recently, the seed catalogs that tantalize gardeners each winter have borne witness to an increasing appreciation of the aesthetic value of grasses. The Manual of Grasses for North America is designed as a successor to the classic volume by Hitchcock and Chase. It reflects current taxonomic thought and includes keys, illustrations, and distribution maps for the nearly 900 native and 400 introduced species that have been found in North America north of Mexico. In addition, it presents keys and illustrations for several species that are known only in cultivation or are of major agricultural significance, either as progenitors of bread wheat and corn or as a major threat to North American agriculture because of their ability to hybridize with crop species. The Manual of Grasses for North America is a major reference work for grasses that will retain its value for many years.
Download or read book Cyclopedia of American Agriculture Crops written by Liberty Hyde Bailey and published by . This book was released on 1907 with total page 784 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Genetic and Historical Relationships Among Geothermally Adapted Agrostis bentgrass of North America and Kamchatka written by Michael T. Tercek and published by . This book was released on 2003 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: Agrostis species have been known to evolve ecotypes rapidly in response to unusual edaphic conditions. The geographic distribution of Agrostis taxa in Lassen Volcanic National Park (California) and Yellowstone National Park (Wyoming) in the United States and the Valley of the Geysers (Kamchatka Peninsula) in Russia suggests that Agrostis scabra might have independently evolved morphologically similar ecotypes several times. We used RAPDs to show that, contrary to expectation, the thermal populations are not independently evolved, but instead constitute a single taxon that currently has four names. A UPGMA including the four thermal and nine nonthermal Agrostis taxa showed that the thermal cluster divides into geographically distinct subclusters, but that two morphologically distinct thermal taxa do not cluster independently. Even though currently confused with the thermal populations, nonthermal A. scabra is not closely related. An analysis of molecular variance (AMOVA) showed significant differentiation between the thermal populations and the nonthermal species sampled in this study. Splitting a hypothesized thermal operational taxonomic unit (OTU) into its components (geographically separated populations) does not greatly affect the partitioning of variation among OTUs. All thermal populations therefore should be assigned to the same taxon, but its taxonomic rank cannot be determined at this time.
Download or read book Bulletin written by United States. Bureau of Plant Industry and published by . This book was released on 1904 with total page 888 pages. Available in PDF, EPUB and Kindle. Book excerpt:
