DOCSLIB.ORG

SB434 Dutch Elm Disease and Its

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
SB434 Dutch Elm Disease and Its AGRICULTURAL EXPERIMENT STATION KANSAS STATE UNIVERSITY OF AGRICULTURE AND APPLIED SCIENCE - MANHATTAN GLENN H. BECK, Director Dutch Elm Disease and Its Control in Kansas 1 PADY 3 4 INTRODUCTION H. E. THOMPSON,2 S. M. and R. A. KEEN Dutch elm disease was discovered in Kansas in October, 1957, in Kansas City, Kan., and has been spreading rapidly since then. This information was prepared because the disease attacks American elm, an important shade and ornamental tree. The disease is caused by a fungus that is carried from elm to elm by bark beetles. Control measures are aimed at destroying the bark beetle. Although the control procedures recommended will not completely prevent the spread of Dutch elm disease, a community program including all phases of control will reduce the annualNEMAHA loss BROWN of elms to a reasonable level. JACKSON 1957 �RSON MARION 1958 HARVEY 1960 1959 Fig. 1. Map of known locations of Dutch elm disease in Kansas. 1. Contribution No. 783, Department of Entomology; No. 571, Department of Botany and Plant Pathology; and No. 310, Department of Horticulture, Kansas Agricultural Experiment Station, Manhattan. 2. Assistant professor, Department of Entomology. 3. Professor, bead, Department of Botany and Plant Pathology. 4. Associate professor, Department of Horticulture. (3) Dutch Elm Disease and Its Control in Kansas 1 PADY 3 4 INTRODUCTION H. E. THOMPSON,2 S. M. and R. A. KEEN Dutch elm disease was discovered in Kansas in October, 1957, in Kansas City, Kan., and has been spreading rapidly since then. This information was prepared because the disease attacks American elm, an important shade and ornamental tree. The disease is caused by a fungus that is carried from elm to elm by bark beetles. Control measures are aimed at destroying the bark beetle. Although the control procedures recommended will not completely prevent the spread of Dutch elm disease, a community program including all phases of control will reduce the annualNEMAHA loss BROWN of elms to a reasonable level. JACKSON 1957 �RSON MARION 1958 HARVEY 1960 1959 Fig. 1. Map of known locations of Dutch elm disease in Kansas. 1. Contribution No. 783, Department of Entomology; No. 571, Department of Botany and Plant Pathology; and No. 310, Department of Horticulture, Kansas Agricultural Experiment Station, Manhattan. 2. Assistant professor, Department of Entomology. 3. Professor, bead, Department of Botany and Plant Pathology. 4. Associate professor, Department of Horticulture. (3) I""I..V'L\.LVUL.LUL\.rt.L .a..:.,.Ar.C,,L\.l.1.V.l.C...L�.l lJJ..rt.J..lU.1.� .tlULLETIN 404: LJUTCH J:!.LM LJISEASE ---- :rc".��i:c ( Fig. 2). The fungus continues to History of the Disease WILTINI live in dead trees and bark beetles continue their tunneling. The fungus First described in Holland in 1921, grows and sporulates especially in its the disease marched across Europe in /,�, .., I :�:; ..,,.. .. .. ..,... Graphium stage with its sticky masses 10 years. In 1930 it was found on SPRING SUMMER of spores ( Fig. 5). In May when four dead trees in Cleveland, Ohio, ,. .. rn•• the beetles emerge they carry the and by 1933, in New York, New Jer­ ADULTI U,\1�\S ____.,_ ___ _ spores to healthy trees and infect LARVAE sey, Connecticut, Pennsylvania, and IN DEAD JWOOi) them. Later beetle emergences are Maryland. By 1957 it was found in FALL Kansas City, Mo. Three positive col­ lections of the disease were made in Wyandotte and Johnson counties, Kansas, in October, 1957. In 1958 it ,uNeus OVERWINTERS IN was found in Leavenworth and Miami IROOO ULLERIU counties; during 1959, in Franklin, Douglas, Lyon, Cherokee, and Mont­ Fig. 3. Seasonal relationship between gomery counties; during 1960, in life history of the smaller European elm Atchison, Anderson, Allen, Bourbon, barkcause beetle Dutch and elmDutch disease elm disease. 6 but only Crawford, Linn, Neosho, Shawnee the first two are important in the U.S. counties ( Fig. 1). There is every Both grow, in dead elm wood, and indication that the disease is rapidly particularly in the tunnels made by increasing in the eastern third of Kan­ the beetles. Spores stick to beetles sas. It is present from the Atlantic and can live on them 3 months at 10- 0 coast west to Kansas, Nebraska and 20 C. and for 2 years in fresh frozen Oklahoma, and from eastern Quebec Fig. 2. Infected tree near Osawatomie beetles. Kansas, shows typical symptoms of Dutch Infection takes place only through and Ontario to the southeastern states. elm disease. The limb in the center already is dead; the left limb has wilted leaves and wounds made by bark beetles in May Symptoms of the Disease partial defoliation, while the right limb is ( Fig. 4a). Healthy bark does not wilting. The disease has since spread to Dutch elm disease is impossible to become infected. When beetles leave theproof elms of inthe the disease. background. Where the dis­ identify positively by sight, but its infected elm wood and fly to healthy ease is unknown, the fungus must be symptoms include: elms, they carry the spores with them. isolated to be sure the tree died from As they burrow into the bark and Dutch elm disease. wood, the spores are deposited in the a. Many dead branches on a tree or 5 a portion of a tree. Life Cycle of the Fungus tissues of the tree and immediately b. Leaves wilting, frequently turning start to grow. The fungus develops yellow or brown, and falling off early Dutch elm disease is the result of ( Fig. 2). ( Note: Other diseases, an unusual partnership, a beetle rapidly and grows into the bark, the drouth, and bark beetles also may cambium, and the wood. When the cause this.) working with a fungus ( Fig. 3) that c. Weak growth of new branches. parasitizes elm trees but does not fungus is present in the large vessels d. Brownish coloring of outer rings of of spring wood, spores are produced the wood. ( Occasionally this symp­ harm the beetles. The beetles carry and carried rapidly up into the Piecestom doesof suspected not appear; elms also, otherare cul­dis­ fungus spores from infected wood to eases may cause browning.) branches where they infect new wood tured in a laboratory to determine if healthy trees. After the spores are in­ and cause it to turn a brownish color the Dutch elm disease fungus is pres­ troduced into the tissues by the Fig. 4a (left). Beetles feeding through ( Fig. 4b). A limb may wilt and die wounds such as this, introduce the Dutch ent. The fungus also may be isolated beetles, infection occurs. or the entire tree may die suddenly elm disease fungus into healthy tree. from beetles and tunnel debris. A Three kinds of infectious spores (Courtesy of Dept. of Entomology, Cornell University.) tree dying with beetles present is not Fig. 4b (right). Infected sapwood be­ 6. These are referred to as the Graphium, comes discolored around the infected sap­ 5. Ceratocystis ulmi (Buis.) Moreau. Cephalosporium, and Ceratocystis stages. conducting vessels. I""I..V'L\.LVUL.LUL\.rt.L .a..:.,.Ar.C,,L\.l.1.V.l.C...L�.l lJJ..rt.J..lU.1.� .tlULLETIN 404: LJUTCH J:!.LM LJISEASE ---- :rc".��i:c ( Fig. 2). The fungus continues to History of the Disease WILTINI live in dead trees and bark beetles continue their tunneling. The fungus First described in Holland in 1921, grows and sporulates especially in its the disease marched across Europe in /,�, .., I :�:; ..,,.. .. .. ..,... Graphium stage with its sticky masses 10 years. In 1930 it was found on SPRING SUMMER of spores ( Fig. 5). In May when four dead trees in Cleveland, Ohio, ,. .. rn•• the beetles emerge they carry the and by 1933, in New York, New Jer­ ADULTI U,\1�\S ____.,_ ___ _ spores to healthy trees and infect LARVAE sey, Connecticut, Pennsylvania, and IN DEAD JWOOi) them. Later beetle emergences are Maryland. By 1957 it was found in FALL Kansas City, Mo. Three positive col­ lections of the disease were made in Wyandotte and Johnson counties, Kansas, in October, 1957. In 1958 it ,uNeus OVERWINTERS IN was found in Leavenworth and Miami IROOO ULLERIU counties; during 1959, in Franklin, Douglas, Lyon, Cherokee, and Mont­ Fig. 3. Seasonal relationship between gomery counties; during 1960, in life history of the smaller European elm Atchison, Anderson, Allen, Bourbon, barkcause beetle Dutch and elmDutch disease elm disease. 6 but only Crawford, Linn, Neosho, Shawnee the first two are important in the U.S. counties ( Fig. 1). There is every Both grow, in dead elm wood, and indication that the disease is rapidly particularly in the tunnels made by increasing in the eastern third of Kan­ the beetles. Spores stick to beetles sas. It is present from the Atlantic and can live on them 3 months at 10- 0 coast west to Kansas, Nebraska and 20 C. and for 2 years in fresh frozen Oklahoma, and from eastern Quebec Fig. 2. Infected tree near Osawatomie beetles. Kansas, shows typical symptoms of Dutch Infection takes place only through and Ontario to the southeastern states. elm disease. The limb in the center already is dead; the left limb has wilted leaves and wounds made by bark beetles in May Symptoms of the Disease partial defoliation, while the right limb is ( Fig. 4a). Healthy bark does not wilting. The disease has since spread to Dutch elm disease is impossible to become infected. When beetles leave theproof elms of inthe the disease. background. Where the dis­ identify positively by sight, but its infected elm wood and fly to healthy ease is unknown, the fungus must be symptoms include: elms, they carry the spores with them. isolated to be sure the tree died from As they burrow into the bark and Dutch elm disease.
Load more

Recommended publications
  • "National List of Vascular Plant Species That Occur in Wetlands: 1996 National Summary."
    Intro 1996 National List of Vascular Plant Species That Occur in Wetlands The Fish and Wildlife Service has prepared a National List of Vascular Plant Species That Occur in Wetlands: 1996 National Summary (1996 National List). The 1996 National List is a draft revision of the National List of Plant Species That Occur in Wetlands: 1988 National Summary (Reed 1988) (1988 National List). The 1996 National List is provided to encourage additional public review and comments on the draft regional wetland indicator assignments. The 1996 National List reflects a significant amount of new information that has become available since 1988 on the wetland affinity of vascular plants. This new information has resulted from the extensive use of the 1988 National List in the field by individuals involved in wetland and other resource inventories, wetland identification and delineation, and wetland research. Interim Regional Interagency Review Panel (Regional Panel) changes in indicator status as well as additions and deletions to the 1988 National List were documented in Regional supplements. The National List was originally developed as an appendix to the Classification of Wetlands and Deepwater Habitats of the United States (Cowardin et al.1979) to aid in the consistent application of this classification system for wetlands in the field.. The 1996 National List also was developed to aid in determining the presence of hydrophytic vegetation in the Clean Water Act Section 404 wetland regulatory program and in the implementation of the swampbuster provisions of the Food Security Act. While not required by law or regulation, the Fish and Wildlife Service is making the 1996 National List available for review and comment.
    [Show full text]
  • Louisiana Certified Habitat Plant List Native Woody Plants (Trees
    Louisiana Certified Habitat Plant List Native Woody Plants (trees, shrubs, woody vines) Common name Scientific name Stewartia Gum, Swamp Black Nyssa biflora Camellia, Silky malacodendron Acacia, Sweet Acacia farnesiana Catalpa Gum, Tupelo Nyssa aquatica Liquidambar Alder, Black/Hazel Alnus rugosa Catalpa, Southern bignonioides Gum, Sweet styriciflua Allspice, Carolina/ Cedar, Eastern Red Juniperus virginiana Sweet Shrub Calycanthus floridus Cedar, Hackberry Celtis laevigata Ashes, Native Fraxinus spp. Atlantic/Southern Chamaecyparis Hawthorn, Native Crataegus spp. White thyoides Hawthorn, Barberry- Ash, Green F. pennsylvanicum Cherry, Black Prunus serotina leaf C. berberifolia Ash, Carolina F. caroliniana Hawthorn, Cherry, Choke Aronia arbutifolia Ash, Pumpkin F. profunda Blueberry C. brachycantha Cherry-laurel Prunus caroliniana Hawthorn, Green C. viridis Ash, White F. americana Chinquapin Castanea pumila Hawthorn, Mayhaw C. aestivalis/opaca Rhododendron Coralbean, Azalea, Pink canescens Eastern/Mamou Erythrina herbacea Hawthorn, Parsley C. marshallii Azalea, Florida Rhododendron Crabapple, Southern Malus angustifolia Hickories, Native Carya spp. Flame austrinum Creeper, Trumpet Campsis radicans Hickory, Black C. texana Anise, Star Illicium floridanum Parthenocissus Anise, Hickory, Bitternut C. cordiformes Creeper, Virginia quinquefolia Yellow/Florida Illicium parviflorum Hickory, Mockernut C. tomentosa Azalea, Florida Rhododendron Crossvine Bignonia capreolata Flame austrinum Hickory, Nutmeg C. myristiciformes Cucumber Tree Magnolia acuminata Rhododendron Hickory, PECAN C. illinoensis Azalea, Pink canescens Cypress, Bald Taxodium distichum Hickory, Pignut C. glabra Rhododendron Cypress, Pond Taxodium ascendens serrulatum, Hickory, Shagbark C. ovata Cyrilla, Swamp/Titi Cyrilla racemiflora viscosum, Hickory, Azalea, White oblongifolium Cyrilla, Little-leaf Cyrilla parvifolia Water/Bitter Pecan C. aquatica Baccharis/ Groundsel Bush Baccharis halimifolia Devil’s Walkingstick Aralia spinosa Hollies, Native Ilex spp. Baccharis, Salt- Osmanthus Holly, American I.
    [Show full text]
  • Outline of Angiosperm Phylogeny
    Outline of angiosperm phylogeny: orders, families, and representative genera with emphasis on Oregon native plants Priscilla Spears December 2013 The following listing gives an introduction to the phylogenetic classification of the flowering plants that has emerged in recent decades, and which is based on nucleic acid sequences as well as morphological and developmental data. This listing emphasizes temperate families of the Northern Hemisphere and is meant as an overview with examples of Oregon native plants. It includes many exotic genera that are grown in Oregon as ornamentals plus other plants of interest worldwide. The genera that are Oregon natives are printed in a blue font. Genera that are exotics are shown in black, however genera in blue may also contain non-native species. Names separated by a slash are alternatives or else the nomenclature is in flux. When several genera have the same common name, the names are separated by commas. The order of the family names is from the linear listing of families in the APG III report. For further information, see the references on the last page. Basal Angiosperms (ANITA grade) Amborellales Amborellaceae, sole family, the earliest branch of flowering plants, a shrub native to New Caledonia – Amborella Nymphaeales Hydatellaceae – aquatics from Australasia, previously classified as a grass Cabombaceae (water shield – Brasenia, fanwort – Cabomba) Nymphaeaceae (water lilies – Nymphaea; pond lilies – Nuphar) Austrobaileyales Schisandraceae (wild sarsaparilla, star vine – Schisandra; Japanese
    [Show full text]
  • Fables and Foibles of the Coexistence Approach
    bioRxiv preprint doi: https://doi.org/10.1101/016378; this version posted March 10, 2015. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC 4.0 International license. Grimm et al.; Fables and Foibles of the Coexistence Approach Fables and foibles: a critical analysis of the Palaeoflora database and the Coexistence approach for palaeoclimate reconstruction Guido W. Grimm1,*, Johannes M. Bouchal1,2, Thomas Denk2, Alastair J. Potts3 1 University of Vienna, Department of Palaeontology, Wien; [email protected] 2 Swedish Museum of Natural History, Department of Palaeobiology, Stockholm 3 Nelson-Mandela Metropolitan University, Botany Department, Port Elizabeth * Corresponding author 1 bioRxiv preprint doi: https://doi.org/10.1101/016378; this version posted March 10, 2015. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC 4.0 International license. Grimm et al.; Fables and Foibles of the Coexistence Approach Abstract The “Coexistence Approach” is a mutual climate range (MCR) technique combined with the nearest-living relative (NLR) concept. It has been widely used for palaeoclimate reconstructions based on Eurasian plant fossil assemblages, most of them palynofloras (studied using light microscopy). The results have been surprisingly uniform, typically converging to subtropical, per-humid or monsoonal conditions. Studies based on the coexistence approach have had a marked impact in literature, generating over 10,000 citations thus far.
    [Show full text]
  • Contribution to the Biosystematics of Celtis L. (Celtidaceae) with Special Emphasis on the African Species
    Contribution to the biosystematics of Celtis L. (Celtidaceae) with special emphasis on the African species Ali Sattarian I Promotor: Prof. Dr. Ir. L.J.G. van der Maesen Hoogleraar Plantentaxonomie Wageningen Universiteit Co-promotor Dr. F.T. Bakker Universitair Docent, leerstoelgroep Biosystematiek Wageningen Universiteit Overige leden: Prof. Dr. E. Robbrecht, Universiteit van Antwerpen en Nationale Plantentuin, Meise, België Prof. Dr. E. Smets Universiteit Leiden Prof. Dr. L.H.W. van der Plas Wageningen Universiteit Prof. Dr. A.M. Cleef Wageningen Universiteit Dr. Ir. R.H.M.J. Lemmens Plant Resources of Tropical Africa, WUR Dit onderzoek is uitgevoerd binnen de onderzoekschool Biodiversiteit. II Contribution to the biosystematics of Celtis L. (Celtidaceae) with special emphasis on the African species Ali Sattarian Proefschrift ter verkrijging van de graad van doctor op gezag van rector magnificus van Wageningen Universiteit Prof. Dr. M.J. Kropff in het openbaar te verdedigen op maandag 26 juni 2006 des namiddags te 16.00 uur in de Aula III Sattarian, A. (2006) PhD thesis Wageningen University, Wageningen ISBN 90-8504-445-6 Key words: Taxonomy of Celti s, morphology, micromorphology, phylogeny, molecular systematics, Ulmaceae and Celtidaceae, revision of African Celtis This study was carried out at the NHN-Wageningen, Biosystematics Group, (Generaal Foulkesweg 37, 6700 ED Wageningen), Department of Plant Sciences, Wageningen University, the Netherlands. IV To my parents my wife (Forogh) and my children (Mohammad Reza, Mobina) V VI Contents ——————————— Chapter 1 - General Introduction ....................................................................................................... 1 Chapter 2 - Evolutionary Relationships of Celtidaceae ..................................................................... 7 R. VAN VELZEN; F.T. BAKKER; A. SATTARIAN & L.J.G. VAN DER MAESEN Chapter 3 - Phylogenetic Relationships of African Celtis (Celtidaceae) ........................................
    [Show full text]
  • Vegetation Community Monitoring at Ocmulgee National Monument, 2011
    National Park Service U.S. Department of the Interior Natural Resource Stewardship and Science Vegetation Community Monitoring at Ocmulgee National Monument, 2011 Natural Resource Data Series NPS/SECN/NRDS—2014/702 ON THE COVER Duck potato (Sagittaria latifolia) at Ocmulgee National Monument. Photograph by: Sarah C. Heath, SECN Botanist. Vegetation Community Monitoring at Ocmulgee National Monument, 2011 Natural Resource Data Series NPS/SECN/NRDS—2014/702 Sarah Corbett Heath1 Michael W. Byrne2 1USDI National Park Service Southeast Coast Inventory and Monitoring Network Cumberland Island National Seashore 101 Wheeler Street Saint Marys, Georgia 31558 2USDI National Park Service Southeast Coast Inventory and Monitoring Network 135 Phoenix Road Athens, Georgia 30605 September 2014 U.S. Department of the Interior National Park Service Natural Resource Stewardship and Science Fort Collins, Colorado The National Park Service, Natural Resource Stewardship and Science office in Fort Collins, Colorado, publishes a range of reports that address natural resource topics. These reports are of interest and applicability to a broad audience in the National Park Service and others in natural resource management, including scientists, conservation and environmental constituencies, and the public. The Natural Resource Data Series is intended for the timely release of basic data sets and data summaries. Care has been taken to assure accuracy of raw data values, but a thorough analysis and interpretation of the data has not been completed. Consequently, the initial analyses of data in this report are provisional and subject to change. All manuscripts in the series receive the appropriate level of peer review to ensure that the information is scientifically credible, technically accurate, appropriately written for the intended audience, and designed and published in a professional manner.
    [Show full text]
  • And Baldcypress (Taxodium Distichum)
    Louisiana State University LSU Digital Commons LSU Master's Theses Graduate School 2012 Evaluation of growth rates and establishment patterns of water-elm (Planera aquatica) and baldcypress (Taxodium distichum) in response to hydrologic and climatic conditions at Catahoula Lake, Louisiana Sanjeev Joshi Louisiana State University and Agricultural and Mechanical College, [email protected] Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_theses Part of the Environmental Sciences Commons Recommended Citation Joshi, Sanjeev, "Evaluation of growth rates and establishment patterns of water-elm (Planera aquatica) and baldcypress (Taxodium distichum) in response to hydrologic and climatic conditions at Catahoula Lake, Louisiana" (2012). LSU Master's Theses. 2103. https://digitalcommons.lsu.edu/gradschool_theses/2103 This Thesis is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Master's Theses by an authorized graduate school editor of LSU Digital Commons. For more information, please contact [email protected]. EVALUATION OF GROWTH RATES AND ESTABLISHMENT PATTERNS OF WATER- ELM (PLANERA AQUATICA) AND BALDCYPRESS (TAXODIUM DISTICHUM) IN RESPONSE TO HYDROLOGIC AND CLIMATIC CONDITIONS AT CATAHOULA LAKE, LOUISIANA A Thesis Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in partial fulfillment of the requirements for the degree of Master of Science in The School of Renewable Natural Resources by Sanjeev Joshi B.S. Tribhuvan University, 2008 December 2012 ACKNOWLEDGEMENTS First and foremost, I would like to thank my advisor Dr. Sammy King, for being such a candid mentor, guide and educator not only in the formal arenas of science but also informally in all walks of life especially from the day I first stepped in USA.
    [Show full text]
  • Dutch Elm Disease
    Dutch elm disease A biosecurity threat to Australian elm trees Background Dutch elm disease (DED), caused by the fungi Building resilienceBuilding and biosecurity capacity Ophiostoma ulmi and Ophiostoma novo-ulmi, is considered one of the most devastating tree diseases in the world. These pathogens cause a wilt disease of elm trees (Ulmus spp.) and are vectored between trees by bark beetles. The fungus can also spread from infected to healthy trees by root grafts. The pathogens are not known to occur in Australia but O. novo-ulmi Nursery levy at work: work: levy at Nursery and its vector, the European bark beetle (Scolytus multistriatus), have been present in New Zealand since 1989. This bark beetle has been present in Australia since 1974. The presence of the disease in New Zealand, and the failure to eradicate the disease in that country, is of particular concern to Australia. Elms in Australia are an important feature of many urban landscapes and have considerable amenity and heritage value. They have often been planted in Avenues of Honour to commemorate Australia’s fallen soldiers. Australia now has one of the finest populations of European elm trees remaining in the world. DED, if introduced, may have a large impact on these Australian elms. Pathogens The fungus, O.ulmi, a relatively weak pathogen of elms, was responsible for the first outbreak Young elm infected with DED. Photo by Chad Giblin, of DED in Europe in the early 1900s. The much Department of Forestry Research, University of Minnesota. more aggressive pathogen O. novo - ulmi was described in 1991.
    [Show full text]
  • Additions to the Flora of the Green River Formation
    ADDITIONS TO THE FLORA OF THE GREEN RIVER FORMATION By ROLAND Vol. BROWN This paper adds a number of new species to those office); the Smith ranch (on Greasewood Creek 40 ;already described by other workers as belonging to the miles southwest of Meeker); and on Carr Creek and flora of the Green River formation. Most of the new Brush Creek (30 nllies l10rthwest of De Beque), species were collected by Prof. O. M. Ball, of the Colorado; and north of White River, Utah. Agricultural and Mechanical College of Texas, during Lesquereux 3 included the first description of the the SUl1uners of 1924 to 1926, in the region 'between Green River in his "Tertiary flora" and devoted a the headwaters of Carr and Brush Creeks, 30 lniles .chapter to it in his later volume, "Cretaceous and northwest of De Beque, Colo.1 Tertiary floras," but many of the plants which he The study of this new lna~erial further confirms the regarded as belonging to the Green River formation' opinion expressed by Iillowlton 2 that the Green have since been found by a strict definition of the River :floral remains represent a mixture of elelnents fornlation to belong at other horizons. froITl wann lowland and cool upland ecologic provinces. Newberry 4 added a number of species to Lesquer­ 'The presence of conifers in this flora, hitherto indicated eux's list. ·only by pollen grains in the oil shale, is now further ICnowlto"'n 5 in 1923 assembled the scattered infor­ ·established by the finding of what appear to be conif­ mation on this flora, passed critical judgment upon it, erous leaves (pI.
    [Show full text]
  • A Critical Analysis of the Palaeoflora Database and the Coexistence
    PALBO-03764; No of Pages 20 Review of Palaeobotany and Palynology xxx (2016) xxx–xxx Contents lists available at ScienceDirect Review of Palaeobotany and Palynology journal homepage: www.elsevier.com/locate/revpalbo Fables and foibles: A critical analysis of the Palaeoflora database and the Coexistence Approach for palaeoclimate reconstruction Guido W. Grimm a,⁎, Johannes M. Bouchal a,b,ThomasDenkb,AlastairPottsc a University of Vienna, Department of Palaeontology, Althanstrasse 14 (UZA II), 1090 Wien, Austria b Swedish Museum of Natural History, Department of Palaeobiology, P.O.Box 5007, 10405 Stockholm, Sweden c Nelson-Mandela Metropolitan University, Centre for Coastal Palaeoscience and Botany Department, PO Box 77000, Port Elizabeth 6031, South Africa article info abstract Article history: The ‘Coexistence Approach’ is a mutual climate range (MCR) technique combined with the nearest-living relative Received 10 March 2015 (NLR) concept. It has been widely used for palaeoclimate reconstructions based on Eurasian plant fossil assem- Received in revised form 25 June 2016 blages; most of them palynofloras (studied using light microscopy). The results have been surprisingly uniform, Accepted 1 July 2016 typically converging to subtropical, per-humid or monsoonal conditions. Studies based on the Coexistence Ap- Available online xxxx proach have had a marked impact in literature, generating over 10,000 citations thus far. However, recent studies Keywords: have pointed out inherent theoretical and practical problems entangled in the application of this widely used Coexistence Approach method. But so far little is known how results generated by the Coexistence Approach are affected by subjective Mutual climate range techniques errors, data errors, and violations of the basic assumptions.
    [Show full text]
  • Downloaded from Brill.Com09/25/2021 01:59:22PM Via Free Access 54 IAWA Journal, Vol
    IAWA Journal, Vol. 31 (1), 2010: 53–66 TORUS-BEARING PIT MEMBRANES IN CERCOCARPUS Roland Dute1,*, Jaynesh Patel1 and Steven Jansen2,3 SUMMARY Intervascular pit membranes of Cercocarpus possess torus thickenings. The thickenings, or pads, consist of lignified, secondary wall material. Torus pad deposition occurs late in cell ontogeny and is not associated with a microtubule plexus. Half-bordered pit pairs between tracheary elements and parenchyma cells often have a torus pad on the membrane surface facing the conducting cell. In contrast, a thick protective layer fills the pit cavity on the side of the parenchyma cell. Ontogeny of the torus thickenings in Cercocarpus represents a third mode of torus de- velopment in eudicots when compared to that occurring in Osmanthus / Daphne and Ulmus /Celtis. Key words: Bordered pit, Cercocarpus, pit membrane, torus, tracheid, vessel element, xylem. INTRODUCTION At one time, intervascular pit membranes in eudicotyledon woods were thought to be exclusively homogeneous. Then, in 1978, Ohtani and Ishida observed torus-bearing pit membranes in three species of Osmanthus (Oleaceae) and in three species of Daphne (Thymelaeaceae). Further work in several laboratories since that time has increased the number of species with torus-bearing pit membranes to 78 distributed within ten genera and five families (Table 1 and literature cited therein). Our laboratory has been concerned with the ontogeny of such pit membranes. These developmental studies were summarized by Coleman et al. (2004). Basically, two mechanisms of torus manufacture were recognized. One method, as illustrated by Osmanthus americanus and Daphne odora, involved a late deposition of torus pads in association with microtubule clusters.
    [Show full text]
  • Genome Size Variation in Elms (Ulmus Spp.)
    HORTSCIENCE 52(4):547–553. 2017. doi: 10.21273/HORTSCI11432-16 Johnson, 1979; Oginuma et al., 1990). Poly- ploidy is rare, and it is known from only two species. U. americana is known to include Genome Size Variation in Elms (Ulmus tetraploids with 2n = 56 (Karrfalt and Karnosky, 1975) as well as diploids (Whittemore and spp.) and Related Genera Olsen, 2011), and Hemiptelea davidii has two 1 reported chromosome numbers, 2n =56(Fu Alan T. Whittemore et al., 1998) and 2n = 84 (Oginuma et al., 1990), U.S. National Arboretum, 3501 New York Avenue NE, Washington, DC presumably tetraploid and hexaploid numbers 20002-1958 based on x = 14. Elms in North America and Europe have Zheng-Lian Xia suffered high mortality from two diseases: U.S. National Arboretum, Room 124, Building 010A, BARC-West, 10300 DED, caused by several species of fungi Baltimore Avenue, Beltsville, MD 20705 native to East Asia (Brasier, 1991, 2001), and elm yellows (elm phloem necrosis), Additional index words. DNA content, elm, flow cytometry, Hemiptelea, Planera, Ulmus, caused by a phytoplasma (Mittempergher, Zelkova 2000; Sinclair, 2000). Because of the horti- cultural importance of elms, there has been Abstract. Elms (Ulmus spp.) are iconic street and landscape trees, but their use is much interest in selection and breeding for currently limited by susceptibility to disease, especially Dutch elm disease (DED). disease tolerance in the genus (Dunn, 2000). Improved access to disease-resistant germplasm will be of great benefit for ongoing To date, elm breeding has mostly in- breeding and selection programs, but these programs have been limited historically by volved species native to Europe and North uncertain relationships among Ulmus species, especially the North American species America, although the fungi that cause DED and their putative Old World relatives.
    [Show full text]