DOCSLIB.ORG

Life History of Peltandra Virginica Author(S): Benjamin Goldberg Source: Botanical Gazette, Vol

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Life History of Peltandra Virginica Author(S): Benjamin Goldberg Source: Botanical Gazette, Vol Life History of Peltandra virginica Author(s): Benjamin Goldberg Source: Botanical Gazette, Vol. 102, No. 4 (Jun., 1941), pp. 641-662 Published by: The University of Chicago Press Stable URL: http://www.jstor.org/stable/2471954 . Accessed: 11/08/2011 10:15 Your use of the JSTOR archive indicates your acceptance of the Terms & Conditions of Use, available at . http://www.jstor.org/page/info/about/policies/terms.jsp JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact [email protected]. The University of Chicago Press is collaborating with JSTOR to digitize, preserve and extend access to Botanical Gazette. http://www.jstor.org VOLUME 102 NUMBER 4 THE BOTANICAL GAZETTE June 1941 LIFE HISTORY OF PELTANDRA VIRGINICA BENJAMIN GOLDBERG (WITH FORTY-NINE FIGURES) Introduction A morphologicalstudy of Peltandravirginica Kunth was made to assemble data which would give a rathercomplete life history of a widespreadplant and a basis forcomparison within and outside the Araceae. Features neglectedor incomplete- ly ascertainedin theplant and the familyas a wholewere studied as fullyas possi- ble. Comparativestudies on the aroids (13, 23) have been of interestsince ENGLER (IO, i i, i2) pointedout that in spite of appreciable variationthere were unifying tendenciesin the group. The only detailed morphologicalaccount of Peltandra(7) deals with part of the developmentof the pollen. Additional reportsinclude a microchemicalstudy of the seed and its germination(i8), a demonstrationthat the seed can germinatein almost total absence of oxygen(8), and an account of seed frequencies(9). Observations Peltandrais foundthroughout the easternUnited States and has been reported west of the MississippiRiver. It is an inhabitantof freshwater marshes, especial- ly along the banks of tidal rivers. The stem is a subterraneanvertical rhizome (figs.I, 2R), cylindrical,and with a diameterin mature,unbranched specimens of 8 cm. The leaves are so compactlyarranged that internodesappear nonexistent. The rhizomesometimes branches (fig. 2B) and the branches become separated fromthe parent plant as thebasal portionof the rhizomedecays. Since branchesas well as parentaxis formerect rhizomes, there results characteristically a clusterof plants. Some rhizomesbear ioo or more adventive roots, which reach a diameterof 641 642 BOTANICAL GAZETTE [JUNE about 7 mm. in theirproximal portions. Roots arise acropetallyon the rhizome (fig.i) and sometimespierce the sheathingleaf bases. Wrinklingof the outercorti- cal tissuesof rootsof seedlingsand older plants occurs,sometimes contracting to almost 50 per cent of the originallength in some regions. 4 -AR L~~~ co 'A JP FIGS. i-8.-Fig. i, plant collectedin October. Fig. 2, branchedplant in dormantstate with roots removed.Fig. 3, longisectionof germinatingseed (CO, cotyledon;L, lumen of haustorialcell). Fig. 4, seedlingi6 days old with cotyledon(CO) still withinpericarp. Figs. 5, 6, transverseand longisections throughapex of maturerhizome. Figs. 7, 8, longisectionsof younginflorescences. Above the concave top of the rhizomeduring most of the year is a large conical terminalbud (fig.i TB) about I 5 cm. long, extendingfrom the top of the rhizome to the soil surface. From thisbud, containingrudiments I5 cm. to 50 y long,only a part of the outer,older, and largerrudiments emerge in late spring;the remain- ing ones, excludingthose which abort duringthe interim,emerge during the fol- I94I] GOLDBERG-PELTANDRA 643 lowingyear. The various regionsof the leaf are clearlydefined. Leaves of mature formand size have a sheath 4.5-6.5 dm. long (includingthe subterraneanportion extendingfrom the soil surfaceto the apex of the rhizome),a stalk 2-4 dm. long, and a sagittateto hastate lamina reachingat timesa lengthof 5 dm. (fromthe acu- minate apex to the roundedbasal lobes) and a widthof 2 dm. The largerinflorescences are about 70 cm. long,from the subterraneanproximal region of attachmentof the peduncle to the distal end of the spathe. The dark green spathe is 20-30 cm. long and extendsa fewcentimeters beyond the inclosed spadix. While thereis much variation,most plants in Maryland are at the height of theirvegetative and floweringactivity by the end of May or early June. After pollination,which occurs at this time,the distal part of the spadix, covered with staminate flowers,disintegrates, together with the distal part of the spathe, marked offby a slightinvagination. The erect inflorescencesbend below the at- tachmentof the spathe to the peduncle,the fruitingspadix finallypointing toward or restingon the soil. The fruits,surrounded by the enlargedbasal part of the spathe, ripenin Augustor September. SEED AND SEEDLING The dark greento brownobovoid fruitsmeasure about I.5 cm. long and i cm. wide, and showan apical scar markingthe formerposition of the style. Withinthe membranouspericarp lies usually one, but sometimesas many as three,seeds im- bedded in a colorlessjelly-like material. To the conspicuous,flattened-globular, micropylar portion of the seed is at- tached an obovoid chalazal appendage about 2-2.5 mm. long, which marks the position of the large haustorial cell of the endosperm. Within the seed lies the large embryonicsporophyte enveloped by the residualendosperm and the almost entirelywithered parent sporophytictissue. The layer of remainingendosperm surroundingthe embryois one cell thick,except in the regionnearest the empty haustorialcell, where it is about seven cells thick. The integumentshave become brownishand shriveled,but the parent sporophytictissue in the chalazal region formsa thickcoat aroundthe emptyhaustorial cell. The pale greencotyledon forms the greaterpart of the embryo,and has almost the same size and shape as the more conspicuousmicropylar portion of the seed. In a deep grooveof the cotyledonnear the apex of the seed lies the narrowlyconi- cal, greenplumule, about 9 mm. long and 3.5 mm. in diameterat its base. It con- tains six or seven foliarstructures. Since it is partlyencircled by the upgrowthof cotyledonarytissue, it formswith the cotyledona compactbody. The radicledoes not forma groupof tissues topographicallydelimited from the surfaceof the rest of the embryo. Occasionallythe hypocotyledonaryportion of the radicle appears on the side of the cotyledonas a poorly definedswelling, I.5 mm. thick and 4-5 644 BOTANICAL GAZETTE [JUNE mm. wide. About I.5 mm. below the base of the plumule on its exposed side lies the primaryroot, a slight rounded protuberanceless than i mm. in diameter. Around the primaryroot the surfaceof the hypocotylis marked by three to five small, circular,partially hyaline areas which indicate the position of adventive root primordia. Usually the seeds germinatein April,but in some cases they germinatein the late summerof the year the ovules werefertilized, and while the fruitsare still at- tached to the parent plant. By the time germinationoccurs the ovary wall is usuallyso decayed that it presentsno mechanicalobstacle to germination.As the plumulerises fromits cotyledonarygroove (fig.3PL), the membranousenvelope (E), consistingof the remains of endospermand integuments,is ruptured. Al- thoughthe primaryroot generallyfails to elongate,it may attain a lengthof 2.5 cm. beforewithering. The adventive roots (fig.3AR) grow and elongate rapidly; the firstones are small and short-lived,those formedlater approach by degreesthe maturesize. Figure 4 shows a seedling,with a few adventiveroots (AR) and the firstthree cauline foliar structures,i6 days aftergermination began. The first emergencewas a bladeless sheathlikestructure about 2 cm. long, the second and thirdpossessed elliptical laminae, and the thirdalone a distinctstalk below the lamina. The primaryaxis increases rapidly in diameter,so that the young rhi- zomes show an obconical tapering. MATURE PLANT BRANCHING.-The seedling behaves as a monopodiumuntil initiationof the firstinflorescence, which is developed directlyfrom the apex of the primaryaxis. Apical growthis thencarried on by a bud whichdevelops in the axil of the penulti- mate leaf. In the axil of the ultimateleaf a second bud is formed,which gives rise only to a basal acroscopic,two-keeled prophyll and a second inflorescenceat its apex. The bud in the axil of the penultimateleaf completelydisplaces the original apex of the shoot in prominenceand central position, so that outwardly the branchingsystem appears unchanged,and the branch developing fromthis bud also ceases its apical growthwith the formationof an inflorescence,after it has given rise to its share of leaves. Apical growthof the plant is then maintainedby a bud in the axil of the penultimateleaf of the branch. The process is continued; and thougha matureplant has an erectvertical rhizome, it is actually composedof superposed branches of increasinglyhigher rank. ENGLER (io), recognizingthe sympodial nature of the shoot in practicallyall the Araceae, regardedthe shoot correspondingto the one arisingfrom the bud in the axil of the penultimateleaf of the Peltandrashoot as a unit in the structureof the plant and called it a Fort- set'ungspross(continuation shoot). As in the primaryaxis of the seedling,a second inflorescence(fig. sB), together witha two-keeledprophyll (P), is bornein the axil of the ultimateleaf (U) of each I94I] GOLDBERG-PELTANDRA 645 continuationshoot.
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]
  • Protecting the Natural Endangered Heritage in Romania, Croatia, Poland and Slovenia
    Available online at http://journals.usamvcluj.ro/index.php/promediu ProEnvironment ProEnvironment 11 (2018) 143-157 Review The Rights of Alive – Protecting the Natural Endangered Heritage in Romania, Croatia, Poland and Slovenia CIOANCĂ Lia-Maria1*, Luminița UJICĂ2, Marijana MIKULANDRA3, Ryszard SOŁTYSIK4, Maja ČERNE5 1Babeș-Bolyai University Cluj-Napoca, University Extension Bistrița, Andrei Mureşanu st., no. 3-5, Romania 2High Scool with Sportive Program Bistrița, Calea Moldovei no. 18. Romania 3OŠ Tina Ujevi Osnovna škola Tina Ujevića Koturaška cesta 75 10000 Zagreb, Croatia 4Zespół Szkół Nr1 w Humniskach, 36 – 206, Huminska 264, Poland 5OŠ Rogaška Slatina, Kidričeva ulica 24, 3250 Rogaška Slatina Slovenia Received 23 July 2018; received and revised form 18 September 2018; accepted 25 September 2018 Available online 30 September 2018 Abstract This article deals with the impact of destructive actions of human population on natural world. As a consequence of relying on non-renewable energy sources and reckless encroachment on natural habitats a lot of plant and animal species have become extinct and more and more species are getting endangered. Thus celebrating biodiversity and solidarity for all life forms, from the tiniest one to the most complex eco-systems, has been in the centre of our attention and operational activities. Keywords: durable development, ecology, endangered species. 1. Introduction Within the massive destruction of forests and forest climate, we witness significant changes, Just as the man has passed from the stage of sometimes radical of the environment. For the animal hunter and collector up to animal raiser and farmer, and plants which have survived through a long period the natural vegetation has increasingly been subject of adaptation, a new difficult era starts again.
    [Show full text]
  • Download/Empfehlung-Invasive-Arten.Pdf
    09-15078 rev FORMAT FOR A PRA RECORD (version 3 of the Decision support scheme for PRA for quarantine pests) European and Mediterranean Plant Protection Organisation Organisation Européenne et Méditerranéenne pour la Protection des Plantes Guidelines on Pest Risk Analysis Lignes directrices pour l'analyse du risque phytosanitaire Decision-support scheme for quarantine pests Version N°3 PEST RISK ANALYSIS FOR LYSICHITON AMERICANUS HULTÉN & ST. JOHN (ARACEAE) Pest risk analyst: Revised by the EPPO ad hoc Panel on Invasive Alien Species Stage 1: Initiation The EWG was held on 2009-03-25/27, and was composed of the following experts: - Ms Beate Alberternst, Projektgruppe Biodiversität und Landschaftsökologie ([email protected]) - M. Serge Buholzer, Federal Department of Economic Affairs DEA ([email protected]) - M. Manuel Angel Duenas, CEH Wallingford ([email protected]) - M. Guillaume Fried, LNPV Station de Montpellier, SupAgro ([email protected]), - M. Jonathan Newman, CEH Wallingford ([email protected]), - Ms Gritta Schrader, Julius Kühn Institut (JKI) ([email protected]), - M. Ludwig Triest, Algemene Plantkunde en Natuurbeheer (APNA) ([email protected]) - M. Johan van Valkenburg, Plant Protection Service ([email protected]) 1 What is the reason for performing the Lysichiton americanus originates from the pacific coastal zone of Northwest-America PRA? and was imported into the UK at the beginning of the 20th century as a garden ornamental, and has since been sold in many European countries, including southern 1 09-15078 rev countries like Italy. It is now found in 11 European countries. The species has been observed to reduce biodiversity in the Taunus region in Germany.
    [Show full text]
  • Vascular Flora of the Possum Walk Trail at the Infinity Science Center, Hancock County, Mississippi
    The University of Southern Mississippi The Aquila Digital Community Honors Theses Honors College Spring 5-2016 Vascular Flora of the Possum Walk Trail at the Infinity Science Center, Hancock County, Mississippi Hanna M. Miller University of Southern Mississippi Follow this and additional works at: https://aquila.usm.edu/honors_theses Part of the Biodiversity Commons, and the Botany Commons Recommended Citation Miller, Hanna M., "Vascular Flora of the Possum Walk Trail at the Infinity Science Center, Hancock County, Mississippi" (2016). Honors Theses. 389. https://aquila.usm.edu/honors_theses/389 This Honors College Thesis is brought to you for free and open access by the Honors College at The Aquila Digital Community. It has been accepted for inclusion in Honors Theses by an authorized administrator of The Aquila Digital Community. For more information, please contact [email protected]. The University of Southern Mississippi Vascular Flora of the Possum Walk Trail at the Infinity Science Center, Hancock County, Mississippi by Hanna Miller A Thesis Submitted to the Honors College of The University of Southern Mississippi in Partial Fulfillment of the Requirement for the Degree of Bachelor of Science in the Department of Biological Sciences May 2016 ii Approved by _________________________________ Mac H. Alford, Ph.D., Thesis Adviser Professor of Biological Sciences _________________________________ Shiao Y. Wang, Ph.D., Chair Department of Biological Sciences _________________________________ Ellen Weinauer, Ph.D., Dean Honors College iii Abstract The North American Coastal Plain contains some of the highest plant diversity in the temperate world. However, most of the region has remained unstudied, resulting in a lack of knowledge about the unique plant communities present there.
    [Show full text]
  • Introduction to Common Native & Invasive Freshwater Plants in Alaska
    Introduction to Common Native & Potential Invasive Freshwater Plants in Alaska Cover photographs by (top to bottom, left to right): Tara Chestnut/Hannah E. Anderson, Jamie Fenneman, Vanessa Morgan, Dana Visalli, Jamie Fenneman, Lynda K. Moore and Denny Lassuy. Introduction to Common Native & Potential Invasive Freshwater Plants in Alaska This document is based on An Aquatic Plant Identification Manual for Washington’s Freshwater Plants, which was modified with permission from the Washington State Department of Ecology, by the Center for Lakes and Reservoirs at Portland State University for Alaska Department of Fish and Game US Fish & Wildlife Service - Coastal Program US Fish & Wildlife Service - Aquatic Invasive Species Program December 2009 TABLE OF CONTENTS TABLE OF CONTENTS Acknowledgments ............................................................................ x Introduction Overview ............................................................................. xvi How to Use This Manual .................................................... xvi Categories of Special Interest Imperiled, Rare and Uncommon Aquatic Species ..................... xx Indigenous Peoples Use of Aquatic Plants .............................. xxi Invasive Aquatic Plants Impacts ................................................................................. xxi Vectors ................................................................................. xxii Prevention Tips .................................................... xxii Early Detection and Reporting
    [Show full text]
  • Aquatic Vascular Plant Species Distribution Maps
    Appendix 11.5.1: Aquatic Vascular Plant Species Distribution Maps These distribution maps are for 116 aquatic vascular macrophyte species (Table 1). Aquatic designation follows habitat descriptions in Haines and Vining (1998), and includes submergent, floating and some emergent species. See Appendix 11.4 for list of species. Also included in Appendix 11.4 is the number of HUC-10 watersheds from which each taxon has been recorded, and the county-level distributions. Data are from nine sources, as compiled in the MABP database (plus a few additional records derived from ancilliary information contained in reports from two fisheries surveys in the Upper St. John basin organized by The Nature Conservancy). With the exception of the University of Maine herbarium records, most locations represent point samples (coordinates were provided in data sources or derived by MABP from site descriptions in data sources). The herbarium data are identified only to township. In the species distribution maps, town-level records are indicated by center-points (centroids). Figure 1 on this page shows as polygons the towns where taxon records are identified only at the town level. Data Sources: MABP ID MABP DataSet Name Provider 7 Rare taxa from MNAP lake plant surveys D. Cameron, MNAP 8 Lake plant surveys D. Cameron, MNAP 35 Acadia National Park plant survey C. Greene et al. 63 Lake plant surveys A. Dieffenbacher-Krall 71 Natural Heritage Database (rare plants) MNAP 91 University of Maine herbarium database C. Campbell 183 Natural Heritage Database (delisted species) MNAP 194 Rapid bioassessment surveys D. Cameron, MNAP 207 Invasive aquatic plant records MDEP Maps are in alphabetical order by species name.
    [Show full text]
  • Witte Moerasaronskelken in Alle Kleuren
    © Werkgroep Aquatische Planten WWW.WATERPLANTEN.ORG Aad Bouman Witte moerasaronskelken in alle kleuren Aronskelken zijn populaire planten, vooral voor in en rond de tuinvijver, maar ook als kamerplant. Aad Boumans voordracht had al twee maal op het programma gestaan, maar nu kwam het er eindelijk van. Een verslag in zwart-wit over soms heel kleurige bloemen. Aronskelkfamilie Voor aquarianen is de aronskelkfamilie (Araceae) heel belangrijk: Cryptocoryne, Lagenandra, Anubias. Als gemeenschappelijk kenmerk hebben ze de vorm van de bloem: een aar die omgeven is door een schutblad (spatha). Soms is het schutblad vergroeid tot een vrijwel dichte koker: bij Cryptocoryne en Lagenandra. Een stuk van het schutblad kan uitgegroeid zijn tot een vlag. Bij Anubias lijkt het schutblad de aar geheel te omgeven, maar al snel ontrolt het zich, waarna de bloeiaar zichtbaar wordt en gemakkelijk toegankelijk voor bestuivende insecten. Bij Moerasaronskelken als Arum, Calla, Lysichiton, Zantedeschia, is het schutblad zeer open. In feite is het dit onderdeel dat de bloem zo aantrekkelijk maakt. Op de eerste dia's werd overigens meteen een plantensoort getoond die niet tot de aronskelken behoort: Acorus. De bloemen hiervan hebben wel een aarvorm, maar er is geen schutblad. Arum De Italiaanse aronskelk (Arum italicum) is een inheemse plant. De planten moeten wat vorst kunnen verdragen. Zodra het begint te vriezen lijkt dat tegen te vallen: de bladeren liggen verlept neer op de grond. Het verval is maar schijn. Zodra het warmer wordt komen ze weer tot leven. De bloem is wit. Er is een speciale cultivar met witte nerven in het blad. Op foto's zagen we de vruchtzetting en de overgang in kleur van de bessen, van groen via oranje naar behoorlijk rood.
    [Show full text]
  • The Evolution of Pollinator–Plant Interaction Types in the Araceae
    BRIEF COMMUNICATION doi:10.1111/evo.12318 THE EVOLUTION OF POLLINATOR–PLANT INTERACTION TYPES IN THE ARACEAE Marion Chartier,1,2 Marc Gibernau,3 and Susanne S. Renner4 1Department of Structural and Functional Botany, University of Vienna, 1030 Vienna, Austria 2E-mail: [email protected] 3Centre National de Recherche Scientifique, Ecologie des Foretsˆ de Guyane, 97379 Kourou, France 4Department of Biology, University of Munich, 80638 Munich, Germany Received August 6, 2013 Accepted November 17, 2013 Most plant–pollinator interactions are mutualistic, involving rewards provided by flowers or inflorescences to pollinators. An- tagonistic plant–pollinator interactions, in which flowers offer no rewards, are rare and concentrated in a few families including Araceae. In the latter, they involve trapping of pollinators, which are released loaded with pollen but unrewarded. To understand the evolution of such systems, we compiled data on the pollinators and types of interactions, and coded 21 characters, including interaction type, pollinator order, and 19 floral traits. A phylogenetic framework comes from a matrix of plastid and new nuclear DNA sequences for 135 species from 119 genera (5342 nucleotides). The ancestral pollination interaction in Araceae was recon- structed as probably rewarding albeit with low confidence because information is available for only 56 of the 120–130 genera. Bayesian stochastic trait mapping showed that spadix zonation, presence of an appendix, and flower sexuality were correlated with pollination interaction type. In the Araceae, having unisexual flowers appears to have provided the morphological precon- dition for the evolution of traps. Compared with the frequency of shifts between deceptive and rewarding pollination systems in orchids, our results indicate less lability in the Araceae, probably because of morphologically and sexually more specialized inflorescences.
    [Show full text]
  • Featured Plants Leucocasia (Formerly Colocasia) Gigantea 'Thailand Giant'
    Spring Spectacular Plant Sale: Featured Plants Leucocasia (formerly Colocasia) gigantea ‘Thailand Giant’, commonly called elephant ear, is a show stopper known for its large size and texture in the landscape. In one growing season individual leaves can reach up to 2 to 4 feet in length and are held up by sturdy, succulent leaf stalks. They can handle part shade, but will not grow as large as they do if planted in full sun. In late summer calla lily-like white flowers provide a pleasant fragrance. Elephant ears should be watered regularly, especially during dry summer months. These giants are fabulous when planted in mixed borders, used as specimen plants, and in large containers. Hydrangea serrata Let’s Dance Cancan™ is a new introduction that is not available in garden centers until next year! This selection features handsome lacecap flowers that are strawberry pink in neutral/alkaline soils and soft lavender in acidic soils. Unlike other serratas this hydrangea combats winter dieback by having the ability to create flower buds along the entire length of the stem instead of only at the top of the stem. It also reblooms faster than others, providing long-lasting color throughout summer. For years Philadelphus coronarius, commonly known as mockorange, has fallen out of favor with gardeners, as its unruly size and unkempt look has limited its placement in smaller gardens. Fret no more! New selections of this old-fashioned favorite have been released that are perfect for any size garden. Illuminati Tower™ mockorange is a selection that grows in a very narrow, upright form that is covered with fragrant white flowers in late spring and early summer.
    [Show full text]
  • Conservation and Management of NORTH AMERICAN MASON BEES
    Conservation and Management of NORTH AMERICAN MASON BEES Bruce E. Young Dale F. Schweitzer Nicole A. Sears Margaret F. Ormes Arlington, VA www.natureserve.org September 2015 The views and opinions expressed in this report are those of the author(s). This report was produced in partnership with the U.S. Department of Agriculture, Forest Service. Citation: Young, B. E., D. F. Schweitzer, N. A. Sears, and M. F. Ormes. 2015. Conservation and Management of North American Mason Bees. 21 pp. NatureServe, Arlington, Virginia. © NatureServe 2015 Cover photos: Osmia sp. / Rollin Coville Bee block / Matthew Shepherd, The Xerces Society Osmia coloradensis / Rollin Coville NatureServe 4600 N. Fairfax Dr., 7th Floor Arlington, VA 22203 703-908-1800 www.natureserve.org EXECUTIVE SUMMARY This document provides a brief overview of the diversity, natural history, conservation status, and management of North American mason bees. Mason bees are stingless, solitary bees. They are well known for being efficient pollinators, making them increasingly important components of our ecosystems in light of ongoing declines of honey bees and native pollinators. Although some species remain abundant and widespread, 27% of the 139 native species in North America are at risk, including 14 that have not been recorded for several decades. Threats to mason bees include habitat loss and degradation, diseases, pesticides, climate change, and their intrinsic vulnerability to declines caused by a low reproductive rate and, in many species, small range sizes. Management and conservation recommendations center on protecting suitable nesting habitat where bees spend most of the year, as well as spring foraging habitat. Major recommendations are: • Protect nesting habitat, including dead sticks and wood, and rocky and sandy areas.
    [Show full text]
  • The Plant List
    the list A Companion to the Choosing the Right Plants Natural Lawn & Garden Guide a better way to beautiful www.savingwater.org Waterwise garden by Stacie Crooks Discover a better way to beautiful! his plant list is a new companion to Choosing the The list on the following pages contains just some of the Right Plants, one of the Natural Lawn & Garden many plants that can be happy here in the temperate Pacific T Guides produced by the Saving Water Partnership Northwest, organized by several key themes. A number of (see the back panel to request your free copy). These guides these plants are Great Plant Picks ( ) selections, chosen will help you garden in balance with nature, so you can enjoy because they are vigorous and easy to grow in Northwest a beautiful yard that’s healthy, easy to maintain and good for gardens, while offering reasonable resistance to pests and the environment. diseases, as well as other attributes. (For details about the GPP program and to find additional reference materials, When choosing plants, we often think about factors refer to Resources & Credits on page 12.) like size, shape, foliage and flower color. But the most important consideration should be whether a site provides Remember, this plant list is just a starting point. The more the conditions a specific plant needs to thrive. Soil type, information you have about your garden’s conditions and drainage, sun and shade—all affect a plant’s health and, as a particular plant’s needs before you purchase a plant, the a result, its appearance and maintenance needs.
    [Show full text]
  • CALLA LILIES for CUT FLOWERS and POTS by James Garner, University Ofgeorgia, Athens, GA
    CALLA LILIES FOR CUT FLOWERS AND POTS by James Garner, University ofGeorgia, Athens, GA The callas are species and hybrids ofthe genus Zantedeschia. The Division: Two-year old rhizomes ofcalla can be lifted and divided calla flower is a spath and spadix type inflorescence of elegant after flowering,when foliagehas died back. Care mustbe takennot beauty. Within this genus, there are both warm- and cool-season to introducebacterialpathogensduring this process. Cut rhizomes types. The warm-season callas are deciduous and include Z. must be cured at 70°-80° with 70-80% relative humidity until a elliottana and Z. albomaculata. The cool-season callas include Z. callus is formed. Cured rhizomes are then stored at 68°-70° for 6-8 aehieopicca and its derivatives. The cool-season types require a weeks prior to planting if dormancy has not been broken. Rhizomes dormancy period, while the warm-season types do not. The warm- are heldat 45°-48° if continued storageis required. Onceshipped, season flowers include a variety of yellow and pink shades, but the cured rhizomesshould be held at 50°-60° prior to planting. cool-season types are predominately white. Callas grow from rhi zomes, modified stems that resemble bulbs, and these are avail Tissueculture: Tissue-cultured explants of new cultivarsare rap able from Florida, California, New Zealand, Holland, Israel, and idly becomingavailablefrom specialtylabs, and rapid multiplica France. They are considered hardy in zones 7-11, but may en tion of new cultivars has been accomplished by these means. counter difficulty surviving in areas with extremely hot summers. Callas may be grown for cut flowers or as flowering potted plants.
    [Show full text]