DOCSLIB.ORG

Weeping Lovegrasses in the Southwest

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Weeping Lovegrasses in the Southwest United States Department of Agriculture Field Guide for Managing Lehmann and Weeping Lovegrasses in the Southwest Forest Southwestern Service Region TP-R3-16-21 September 2014 Cover Photos Top right, Lehmann lovegrass: John M. Randall, The Nature Conservancy, Bugwood.org Left, Lehmann lovegrass: Joseph M. DiTomaso, University of California, Bugwood.org Lower right, weeping lovegrass: James H. Miller, USDA Forest Service, Bugwood.org Lower left, weeping lovegrass: Forest and Kim Starr, U.S. Geological Survey, Bugwood.org The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, age, disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic information, political beliefs, reprisal, or because all or part of an individual’s income is derived from any public assistance program. (Not all prohibited bases apply to all programs.) Persons with disabilities who require alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact USDA’s TARGET Center at (202) 720-2600 (voice and TTY). To file a complaint of discrimination, write to USDA, Director, Office of Civil Rights, 1400 Independence Avenue, SW, Washington, DC 20250-9410 or call (800) 795-3272 (voice) or (202) 720-6382 (TTY). USDA is an equal opportunity provider and employer. Printed on recycled paper Lehmann lovegrass (Eragrostis lehmanniana L.) Weeping lovegrass (Eragrostis curvula (Shrad.) Nees. var. curvula) Grass family (Poaceae), Chloridoideae subfamily, Eragrostideae tribe Lehmann and weeping lovegrasses are introduced forage and agricultural land restoration, after wildfires, highway and soil protection grasses that are becoming invasive in construction, and other ground-disturbing activities. Both southwestern states. They are now listed as noxious weeds lovegrasses have been widely planted along highway rights- in Arizona and portions of New Mexico. This field guide of-way and for range restoration/soil conservation efforts in serves as the U.S. Forest Service’s recommendation for the Chihuahuan and Sonoran Deserts. management of Lehmann and weeping lovegrasses in forests, woodlands, rangelands, desert, and desert scrub Growth Characteristics associated with its Southwestern Region. The Southwestern • Both species are perennial bunchgrasses; normally Region covers Arizona and New Mexico, which together warm season but low winter temperatures may cause have 11 national forests. The Region also includes four these lovegrasses to act as annuals or short-lived national grasslands located in northeastern New Mexico, perennials. western Oklahoma, and the Texas panhandle. • Rapid growth; weeping lovegrass grows mostly in summer and is slow to regrow after it is grazed; Lehmann lovegrass actively grows in spring, summer, Description and fall; it has a moderate growth rate following use. Lehmann lovegrass (synonym: African lovegrass) and • Weeping lovegrass grows erect in bunches, 24 to 60 weeping lovegrass (synonyms: Boer lovegrass, curved inches tall; Lehmann lovegrass grows semi-erect in lovegrass, Catalina lovegrass) are hardy, drought-tolerant bunches 15 to 30 inches tall and tends to root at nodes bunchgrasses originally from South Africa. Both grow (weakly stoloniferous). in dense tufts and have seed heads that grow as an open panicle with lax or drooping branches. Weeping lovegrass • Leaf blades flat to slightly rolled under along margins is slightly taller than Lehmann lovegrass and has longer, (weeping lovegrass 5 to 20 inches long; 0.04 to 0.11 narrower, drooping blades with fine, soft hairs on the inch wide and Lehmann lovegrass 0.8 to 5 inches sheaths near the base of the stem. Lehmann lovegrass has long; width same), Lehmann lovegrass blades are smooth sheaths, and newer shoots near the outer edge of glabrous to slightly scabrous; weeping lovegrass may the tuft tend to grow in a more prostrate form (lying on the have long, soft hairs near the base; ligules are ciliate ground). (Lehmann lovegrass ligule is shorter than weeping lovegrass ligule). Weeping lovegrass has been widely planted and is more • Open, greenish, rebranching panicle (weeping broadly distributed across the United States than Lehmann lovegrass inflorescence is 6 to 14 inches long; lovegrass. During the 1980s and 1990s, weeping lovegrass Lehmann lovegrass inflorescence is 2.75 to 7 inches was the most common grass planted on thousands of long); spikelets have 3 to 12 florets each (lower floret acres held under the Conservation Reserve Program in reduced); spikelets yellowish at maturity; weeping New Mexico, Oklahoma, and Texas. The two lovegrass lovegrass blooms in mid-spring; Lehmann lovegrass species were introduced into the Southwest because of their blooms in late spring. desirable qualities in reducing soil erosion and providing forage. However, some of the traits that allow these grasses • Both reproduce from seed; Lehmann lovegrass seeds to thrive in arid areas have also caused them to be highly require a ripening period before germination; dry heat invasive and unwanted within native plant communities. and a certain level of red light improve the likelihood In the Southwest, these grasses have been planted since for germination. Weeping lovegrass does not require the 1930s and were included in seed mixes used for range fertilization to produce seed; it is an obligate apomitic 1 species. Neither of these lovegrasses reproduces lovegrass is less likely to escape boundaries of planted areas, vegetatively; however, Lehmann lovegrass may root it is very persistent and long lived. at nodes. Ecology Management Impacts/threats Considerable information has long been available Lehmann lovegrass is more likely than weeping regarding how best to plant and manage lovegrasses lovegrass to move beyond planted areas into native plant for various beneficial purposes including grazing, soil communities; however, both grasses are expanding their erosion conservation, roadside stabilization, and mine site range. The natural fire regime in desert communities has reclamation. Conversely, there is much less experience been altered as these species have increased, resulting in and information available concerning how best to control more intense wildfires that occur with greater frequency. these grasses in areas where native grass restoration is Both species are not highly preferred by livestock and a primary management objective. To achieve this goal, wildlife for grazing in comparison to native grasses, which there is general agreement that such an effort will require has allowed them to become increasingly dominant in many several steps taken over a long time horizon. In many native plant communities. situations, it may be impractical to replace lovegrasses where they have become widespread and well established Location in native plant communities. Rather, accepting lovegrass as In southeastern Arizona, Lehmann’s lovegrass is commonly a minor component in the vegetation mix may be a more found growing away from planted areas, especially on practical management strategy. In any case, control and course soils at moderate elevations of 3,000 to 4,500 feet. restoration efforts will require long-term planning, integrated Weeping lovegrass tends to not move far from planted areas management, and followup monitoring. The following and grows in Arizona from 4,900 to 6,500 feet. actions should be considered when planning a management approach for these two lovegrasses: Spread Lehmann and weeping lovegrass both produce huge • Maintain healthy plant communities to help prevent quantities of small-sized seed that accumulate in the soil or limit new infestations. This may involve using seed bank. Seed is spread by wind, water, animals, and improved grazing management practices to prevent vehicles. Lehmann lovegrass seed is initially dormant and excessive grazing and/or reseeding areas with requires 6 to 9 months of after-ripening. Shading inhibits desirable native grasses and forbs after disturbance. germination since the seed also requires exposure to red • Detect, report, and map known Lehmann and weeping light to propagate. In southeastern Arizona, the spread of lovegrass populations. Keep annual records of Lehmann lovegrass is related, in part, to the amount and reported infestations. distribution of summer rain and soil type (spread is more • Develop a specific action plan to meet goals and likely in loamy sand or sandy loam soils). Newly emerged objectives for infested areas, which may include weeping lovegrass must have dependable moisture to eradication of new populations of Lehmann lovegrass survive as dry soils will quickly desiccate seedlings. in sensitive sites, such as those areas known to be Invasive Features habitat for threatened and endangered species, travel corridors, seed pathways, etc. Lehmann lovegrass establishes quickly, produces high quantities of viable seed during its first season of growth, and can spread at a rate of 175 m/year. While weeping 2 Table 1. Management options* Site Physical Methods Cultural Methods Biiological Methods Chemical Methods Roadsides, Disk or plow in agronomic Consider native grass species As of yet, classical Use truck or tractor-mounted fence lines, areas. Repeated mowing is when reseeding rights-of-way. biological control spraying equipment to broadcast or noncrop a suppression option along methods are not treat. Wash underneath vehicle Avoid driving vehicles
Load more

Recommended publications
  • Improved Conservation Plant Materials Released by NRCS and Cooperators Through December 2014
    Natural Resources Conservation Service Improved Conservation Plant Materials Released by Plant Materials Program NRCS and Cooperators through December 2014 Page intentionally left blank. Natural Resources Conservation Service Plant Materials Program Improved Conservation Plant Materials Released by NRCS and Cooperators Through December 2014 Norman A. Berg Plant Materials Center 8791 Beaver Dam Road Building 509, BARC-East Beltsville, Maryland 20705 U.S.A. Phone: (301) 504-8175 prepared by: Julie A. DePue Data Manager/Secretary [email protected] John M. Englert Plant Materials Program Leader [email protected] January 2015 Visit our Website: http://Plant-Materials.nrcs.usda.gov TABLE OF CONTENTS Topics Page Introduction ...........................................................................................................................................................1 Types of Plant Materials Releases ........................................................................................................................2 Sources of Plant Materials ....................................................................................................................................3 NRCS Conservation Plants Released in 2013 and 2014 .......................................................................................4 Complete Listing of Conservation Plants Released through December 2014 ......................................................6 Grasses ......................................................................................................................................................8
    [Show full text]
  • Para Especies Exóticas En México Eragrostis Curvula (Schrad.) Nees, 1841., CONABIO, 2016 1
    Método de Evaluación Rápida de Invasividad (MERI) para especies exóticas en México Eragrostis curvula (Schrad.) Nees, 1841., CONABIO, 2016 Eragrostis curvula (Schrad.) Nees, 1841 Fuente: Tropical Forages E. curvula , es un pasto de origen africano, que se cultiva como ornamental y para detener la erosión; se establece en las orillas de carreteras y ambientes naturales como las dunas. Se ha utilizado contra la erosión, para la producción de forraje en suelos de baja fertilidad y para resiembra en pastizales semiáriados. Presenta abundante producción de semillas, gran capacidad para producir grandes cantidades de materia orgánica tanto en las raíces como en el follaje (Vibrans, 2009). Es capaz de desplazar a la vegetación natural. Favorece la presencia de incendios (Queensland Government, 2016). Información taxonómica Reino: Plantae Phylum: Magnoliophyta Clase: Liliopsida Orden: Poales Familia: Poaceae Género: Eragrostis Nombre científico: Eragrostis curvula (Schrad.) Nees, 1841 Nombre común: Zacate amor seco llorón, zacate llorón, zacate garrapata, amor seco curvado Resultado: 0.5109375 Categoría de invasividad: Muy alto 1 Método de Evaluación Rápida de Invasividad (MERI) para especies exóticas en México Eragrostis curvula (Schrad.) Nees, 1841., CONABIO, 2016 Descripción de la especie Hierba perenne, amacollada, de hasta 1.5 m de alto. Tallo a veces ramificado y con raíces en los nudos inferiores, frecuentemente con anillos glandulares. Hojas alternas, dispuestas en 2 hileras sobre el tallo, con las venas paralelas, divididas en 2 porciones, la inferior envuelve al tallo, más corta que el, y la parte superior muy larga, angosta, enrollada (las de las hojas inferiores arqueadas y dirigidas hacia el suelo); entre la vaina y la lámina.
    [Show full text]
  • Cytotype Associations, Ecological Divergence and Genetic Variation in the Apomictic Complex Paspalum Intermedium Munro Ex Morong (Poaceae)
    Cytotype Associations, Ecological Divergence and Genetic Variation in the Apomictic Complex Paspalum intermedium Munro Ex Morong (Poaceae) Dissertation for the award of the degree “Doctor of Philosophy” Ph.D. Division of Mathematics and Natural Sciences of the Georg-August-Universität Göttingen within the doctoral program Biology of the Georg-August University School of Science (GAUSS) Submitted by Piyal Karunarathne Göttingen, 2018 THESIS COMMITTEE Prof. Dr. Elvira Hörandl Department of Systematics, Biodiversity and Evolution of Plants (with herbarium) Albrecht-von-Haller Institute for Plant Sciences University of Göttingen, Germany Prof. Dr. Holger Kreft Department of Biodiversity, Macroecology & Biogeography Faculty of Forest Sciences and Forest Ecology University of Göttingen, Germany Dr. Diego Hojsgaard Department of Systematics, Biodiversity and Evolution of Plants (with herbarium) Albrecht-von-Haller Institute for Plant Sciences University of Göttingen, Germany MEMBERS OF THE EXAMINATION BOARD Reviewer Prof. Dr. Elvira Hörandl Department of Systematics, Biodiversity and Evolution of Plants (with herbarium), Albrecht-von-Haller Institute for Plant Sciences University of Göttingen, Germany Second Prof. Dr. Holger Kreft reviewer Department of Biodiversity, Macroecology & Biogeography Faculty of Forest Sciences and Forest Ecology University of Göttingen, Germany Further members of the Examination Board Prof. Dr. Stefan Scheu J.F. Blumenbach Institute of Zoology and Anthropology University of Göttingen Prof. Dr. Mark Maraun J.F. Blumenbach Institute of Zoology and Anthropology University of Göttingen Prof. Dr. Thomas Friedl Dept. EPSAG University of Göttingen Dr. Sven Bradler J.F. Blumenbach-Institut für Zoologie und Anthropologie University of Göttingen ii Acknowledgments I would like to place on record my sincere gratitude to Dr. Diego Hojsgaard for choosing me to carry out this research project, his excellent supervision, tremendous help and advice, and for remaining unflappable despite my various crisis.
    [Show full text]
  • Modifying Drivers of Competition to Restore Palmer's Agave in Lehmann Lovegrass Dominated Grasslands
    Modifying Drivers of Competition to Restore Palmer's Agave in Lehmann Lovegrass Dominated Grasslands Item Type text; Electronic Thesis Authors Gill, Amy Shamin Citation Gill, Amy Shamin. (2020). Modifying Drivers of Competition to Restore Palmer's Agave in Lehmann Lovegrass Dominated Grasslands (Master's thesis, University of Arizona, Tucson, USA). Publisher The University of Arizona. Rights Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction, presentation (such as public display or performance) of protected items is prohibited except with permission of the author. Download date 25/09/2021 10:37:11 Link to Item http://hdl.handle.net/10150/648602 MODIFYING DRIVERS OF COMPETITION TO RESTORE PALMER’S AGAVE IN LEHMANN LOVEGRASS DOMINATED GRASSLANDS by Amy Shamin Gill ____________________________ Copyright © Amy Shamin Gill 2020 A Thesis Submitted to the Faculty of the SCHOOL OF NATURAL RESOURCES AND ENVIRONMENT In Partial Fulfillment of the Requirements For the Degree of MASTER OF SCIENCE In the Graduate College THE UNIVERSITY OF ARIZONA 2020 2 Acknowledgments I would like to sincerely thank my graduate advisor, Dr. Elise S. Gornish & Fulbright Foreign Degree Program for providing the opportunity for me to complete my Master’s in Science degree at the University of Arizona. Especially Dr. Elise S. Gornish, who provided constant support, mentoring, guidance throughout my thesis project. I would also like to thank my committee members, Dr. Jeffrey S. Fehmi and Dr. Mitchel McClaran, for their availability and support along the way. Huge call out to the Fulbright Program, International Institute of Education, National Parks Service, Bat Conservation International, & Ancestral Lands Crew for funding, collaborations, and data collection.
    [Show full text]
  • 22. Tribe ERAGROSTIDEAE Ihl/L^Ä Huameicaozu Chen Shouliang (W-"^ G,), Wu Zhenlan (ß^E^^)
    POACEAE 457 at base, 5-35 cm tall, pubescent. Basal leaf sheaths tough, whit- Enneapogon schimperianus (A. Richard) Renvoize; Pap- ish, enclosing cleistogamous spikelets, finally becoming fi- pophorum aucheri Jaubert & Spach; P. persicum (Boissier) brous; leaf blades usually involute, filiform, 2-12 cm, 1-3 mm Steudel; P. schimperianum Hochstetter ex A. Richard; P. tur- wide, densely pubescent or the abaxial surface with longer comanicum Trautvetter. white soft hairs, finely acuminate. Panicle gray, dense, spike- Perennial. Culms compactly tufted, wiry, erect or genicu- hke, linear to ovate, 1.5-5 x 0.6-1 cm. Spikelets with 3 fiorets, late, 15^5 cm tall, pubescent especially below nodes. Basal 5.5-7 mm; glumes pubescent, 3-9-veined, lower glume 3-3.5 mm, upper glume 4-5 mm; lowest lemma 1.5-2 mm, densely leaf sheaths tough, lacking cleistogamous spikelets, not becom- villous; awns 2-A mm, subequal, ciliate in lower 2/3 of their ing fibrous; leaf blades usually involute, rarely fiat, often di- length; third lemma 0.5-3 mm, reduced to a small tuft of awns. verging at a wide angle from the culm, 3-17 cm, "i-^ mm wide, Anthers 0.3-0.6 mm. PL and &. Aug-Nov. 2« = 36. pubescent, acuminate. Panicle olive-gray or tinged purplish, contracted to spikelike, narrowly oblong, 4•18 x 1-2 cm. Dry hill slopes; 1000-1900 m. Anhui, Hebei, Liaoning, Nei Mon- Spikelets with 3 or 4 florets, 8-14 mm; glumes puberulous, (5-) gol, Ningxia, Qinghai, Shanxi, Xinjiang, Yunnan [India, Kazakhstan, 7-9-veined, lower glume 5-10 mm, upper glume 7-11 mm; Kyrgyzstan, Mongolia, Pakistan, E Russia; Africa, America, SW Asia].
    [Show full text]
  • Characterizing the Spatial Distribution of Eragrostis Curvula (Weeping Lovegrass) in New Jersey (United States of America) Using Logistic Regression
    environments Article Characterizing the Spatial Distribution of Eragrostis Curvula (Weeping Lovegrass) in New Jersey (United States of America) Using Logistic Regression Kikombo Ilunga Ngoy * and Daniela Shebitz School of Environmental and Sustainability Sciences, Kean University, Union, NJ 07083, USA; [email protected] * Correspondence: [email protected] Received: 8 August 2019; Accepted: 6 December 2019; Published: 15 December 2019 Abstract: The increasing spread of invasive plants has become a critical driver of global environmental change. Once established, invasive species are often impossible to eradicate. Therefore, predicting the spread has become a key element in fighting invasive species. In this study, we examined the efficiency of a logistic regression model as a tool to identify the spatial occurrence of an invasive plant species. We used Eragrostis curvula (Weeping Lovegrass) as the dependent variable. The independent variables included temperature, precipitation, soil types, and the road network. We randomly selected 68 georeferenced points to test the goodness of fit of the logistic regression model to predict the presence of E. curvula. We validated the model by selecting an additional 68 random points. Results showed that the probability to successfully predict the presence of E. Curvula was 82.35%. The overall predictive accuracy of the model for the presence or absence of E. Curvula was 80.88%. Additional tests including the Chi-square test, the Hosmer–Lemeshow (HL) test, and the area under the curve (AUC) values, all indicated that the model was the best fit. Our results showed that E. curvula was associated with the identified variables. This study suggests that the logistic regression model can be a useful tool in the identification of invasive species in New Jersey.
    [Show full text]
  • Eragrostis Surreyana (Poaceae) an Uncommon, Habitat Restricted New Species from the Pilbara Bioregion of Western Australia
    Telopea 13(1–2) 143–148 Eragrostis surreyana (Poaceae) an uncommon, habitat restricted new species from the Pilbara Bioregion of Western Australia Kelly A. Shepherd and Malcolm E. Trudgen Western Australian Herbarium, Department of Environment and Conservation, Science Division, Locked Bag 104, Bentley Delivery Centre, Western Australia 6983, Australia Author for correspondence: [email protected] Abstract Eragrostis surreyana K.A.Sheph. & Trudgen sp. nov. is a diminutive annual lovegrass named for the late Surrey Jacobs (1946–2009). This species is restricted to seasonal wetland areas in the Pilbara Bioregion of Western Australia. Although it is quite widespread, E. surreyana is currently only known from five locations and it is likely it has suffered loss of populations through habitat degradation caused by sheep and cattle grazing. It is therefore considered to be a species of conservation concern. Eragrostis surreyana produces numerous culms and forms a small tussock. It is distinguished from related species by its flexuose rachilla, ovate lemmas and short hairs along the keel of each palea. A description, images and a map of the distribution of this new species is provided. Introduction The lovegrass genus Eragrostis Wolfis includes around 350 species world wide. Eragrostis has been revised for the Flora of Australia project (Palmer et al. 2005), a treatment that draws on the earlier work by Lazarides (1997). At that time there were 73 species recorded in Australia, of which 15 were considered to be weeds. Based on the current Western Australian Census there are 19 species of Eragrostis in the Pilbara Interim Biogeographic Regionalisation for Australia (IBRA) region, including two Priority Three conservation listed species (E.
    [Show full text]
  • Ecology and Habitat Suitability of Cape Mountain Zebra (Equus Zebra Zebra) in the Western Cape, South Africa
    Ecology and habitat suitability of Cape mountain zebra (Equus zebra zebra) in the Western Cape, South Africa by Adriaan Jacobus Olivier Thesis presented in partial fulfilment of the requirements for the degree Masters of Science at Stellenbosch University Department of Conservation Ecology and Entomology, Faculty of AgriScience Supervisor: Dr Alison J. Leslie Co-supervisor: Dr Jason I. Ransom December 2019 Stellenbosch University https://scholar.sun.ac.za Declaration By submitting this thesis electronically, I declare that the entirety of the work contained therein is my own, original work, that I am the sole author thereof (save to the extent explicitly otherwise stated), that reproduction and publication thereof by Stellenbosch University will not infringe any third party rights and that I have not previously in its entirety or in part submitted it for obtaining any qualification. Jaco Olivier December 2019 Copyright © 2019 Stellenbosch University All rights reserved ii Stellenbosch University https://scholar.sun.ac.za Abstract Endemic to South Africa, the Cape mountain zebra (Equus zebra zebra) historically occurred throughout the Western Cape, and parts of the Northern and Eastern Cape. However, due to human impacts fewer than 50 individuals remained by the 1950’s. Conservation efforts over the past 50 years have resulted in the population increasing to over 4700 individuals and having moved on the IUCN red list, from Critically Endangered to Least Concern. As there are still many isolated meta-populations, CapeNature established a Biodiversity Management Plan for the conservation of Cape mountain zebra in the Western Cape. In 2001, 15 (six males and nine females) Cape mountain zebra was reintroduced into Bakkrans Nature Reserve, situated in the Cederberg Wilderness Area of South Africa.
    [Show full text]
  • Plants, Volume 1, Number 1 (August 1979)
    Desert Plants, Volume 1, Number 1 (August 1979) Item Type Article Publisher University of Arizona (Tucson, AZ) Journal Desert Plants Rights Copyright © Arizona Board of Regents. The University of Arizona. Download date 02/10/2021 01:18:53 Link to Item http://hdl.handle.net/10150/528188 Volume I. Number 1. August 1979 Desert Published by The University of Arizona for the Plants Boyce Thompson Southwestern Arboretum Assisting Nature with Plant Selection4 Larry K. Holzworth Aberrant Sex -Ratios in Jojoba Associated with Environmental Factors 8 Serena L. Cole 'J. G. Lemmon & Wife,' Plant Explorers in Arizona, California, and Nevada12 Frank S. Crosswhite 'Extinct' Wire -Lettuce, Stephanomeria schottii (Compositae), Rediscovered in Arizona after More Than One Hundred Years22 Elinor Lehto Southwestern Indian Sunflowers23 Gary Paul Nabhan Transition from a Bermudagrass Lawn to a Landscape of Rock or Gravel Mulch 27 Charles Sacamano Preliminary Evaluation of Cold- hardiness in Desert Landscaping Plants at Central Arizona College29 William A. Kinnison Effects of the 1978 Freeze on Native Plants of Sonora, Mexico33 Warren D. Jones The Severe Freeze of 1978 -79 in the Southwestern United States37 The National Climate Program Act of 197840 Reviews42 Arboretum Progress46 R. T. McKittrick Volume 1. Number 1. August 1979 Published by The University of Arizona Desert Plants for the Boyce Thompson Southwestern Arboretum The Severe Freeze of 1978 -79 in the Contents Southwestern United States37 Correspondents: Editorial Barrie D. Coate, Saratoga Horticultural Foundation; Dara E. Emery, Santa Barbara Botanic Garden; Louis C. Assisting Nature with Plant Selection 4 Erickson, Botanic Gardens, University of California, River- Larry K. Holzworth, USDA Soil Conservation side; Wayne L.
    [Show full text]
  • Host Specificity of Ischnodemus Variegatus, an Herbivore of West
    BioControl DOI 10.1007/s10526-008-9188-3 Host specificity of Ischnodemus variegatus, an herbivore of West Indian marsh grass (Hymenachne amplexicaulis) Rodrigo Diaz Æ William A. Overholt Æ James P. Cuda Æ Paul D. Pratt Æ Alison Fox Received: 31 January 2008 / Accepted: 17 July 2008 Ó International Organization for Biological Control (IOBC) 2008 Abstract West Indian marsh grass, Hymenachne to suboptimal hosts occurred in an area where amplexicaulis Rudge (Nees) (Poaceae), is an emer- H. amplexicaulis was growing in poor conditions gent wetland plant that is native to South and Central and there was a high density of I. variegatus. Thus, America as well as portions of the Caribbean, but is laboratory and field studies demonstrate that considered invasive in Florida USA. The neotropical I. variegatus had higher performance on H. amplexi- bug, Ischnodemus variegatus (Signoret) (Hemiptera: caulis compared to any other host, and that suboptimal Lygaeoidea: Blissidae) was observed feeding on hosts could be colonized temporarily. H. amplexicaulis in Florida in 2000. To assess whether this insect could be considered as a specialist Keywords Blissidae Á Hemiptera Á Herbivore biological control agent or potential threat to native performance Á Host quality Á Poaceae and cultivated grasses, the host specificity of I. variegatus was studied under laboratory and field conditions. Developmental host range was examined Introduction on 57 plant species across seven plant families. Complete development was obtained on H. amplexi- West Indian marsh grass, Hymenachne amplexicaulis caulis (23.4% survivorship), Paspalum repens (0.4%), Rudge (Nees) (Poaceae), is a perennial emergent Panicum anceps (2.2%) and Thalia geniculata weed in wetlands of Florida USA and northeastern (0.3%).
    [Show full text]
  • Alien Species of Eragrostis P. Beauv. ID the British Isles
    Wa/sollia.I3.III-117(1980l 111 Alien species of Eragrostis P. Beauv. ID the British Isles T. B. RYVES 44 Galsworthy Road, Kingston Hil/, Surrey ABSTRACT A key to a nd an annotated list of all 51 species of Eragroslis P. Beauv. which are known to have occurred in the British Isles are given. INTRODUCTION This paper provides a key to and an annotated list of the 51 species of Eragrostis P. Beauv. known to have occurred in the British Isles. At present there is no readily available key to these species, which originate from many parts of the world. Species of Eragrostis bear a superficial resemblance to those of Poa, both genera having unawned compressed spikelets consisting of many f1orets. However, the former differ in having 3-nerved lemmas (5-nerved in Poa), ligules which are nearly always ciliate or absent (membranous or almost absent in Poa), pointed leaves (often blunt in Poa), and no basal cottony hairs on the callus of the lemma (possessed by some species of Poa). There are at least 300 species of Eragroslis (some authorities give twice that number, according to taxonomic opinion) distributed over the warm-temperate and tropical regions of the world. Less than a dozen species are established in central and southern Europe, being mostly annuals which fruit freely in hot summers and with seeds that survive cold winters. Only one is established in the British Isles (in the Channel Islands) (McClintock 1975) but several other species, occurring as casuals, may occasionally set seed or even survive a mild winter.
    [Show full text]
  • A Preliminary Vegetation Classification of the Tombstone, Arizona, Vicinity
    AN ABSTRACT OF THE THESIS OF EDMUNDO GARCIA-MOYA for theDOCTOR OF PHILOSOPHY (Name) (Degree) ANIMAL SCIENCE in (RANGELAND RESOURCES) presented onfi,?,(2;2-01) / Yj) Qi (Major) (Date) Title: A PRELIMINARY VEGETATION CLASSIFICATION OF THE TOMBSTONE, ARIZONA, VICINITY Redacted for Privacy Abstract approved: C. E. Poulton The need for classifying vegetation in a more precise wayis evident.Also, there is a need to provide a hierarchicalclassification scheme that will match changes in image characteristics as one moves through the scales from spaceto conventional aerial photo- graphy.Such refined classifications of vegetation are thefirst steps toward a better understanding of the potentialities andlimitations of a specified area which help in the detection of analogousenvironmental conditions for resource allocation and management purposes.These needs become more urgent as use and competitionfor natural resources and land increases.The first approximation of a classification scheme may meet these needs for a test site inthe Tombstone, Arizona, vicinity.This classification task was accomplished by the use of a "hierarchical- polythetic-agglomerative" package using presence-absence data and standardized cover esti- mates, The following tentative associations and a variant were found upon division of the original data into groups of convenient size to meet the limitations of the programs: Association A (Panicum hirticaule/Tidestromia lanuginosa- Boerhaavia coulteri) la (a variant of Association A) Association B (Rhus microphylla-Dalea formosa)
    [Show full text]