3,99 €
Mehr erfahren.
- Herausgeber: iOnlineShopping.com
- Kategorie: Wissenschaft und neue Technologien
- Sprache: Englisch
- Veröffentlichungsjahr: 2019
This simple key and guide to the woody plants—trees, shrubs and woody vines—which grow naturally in Dallas County, Texas, has been prepared to help beginners of any age in getting better acquainted with these leafy neighbors and friends. Woody plants offer one of the best places to begin a study of nature: first because there are but few kinds to learn in comparison with many other living forms—about 90 of these plants against estimated numbers for the county of about 300 birds, 500 to 1000 other flowering plants and over 25,000 insects; second, woody plants remain in one place, freely available for observation at any hour or season and year after year—if they escape human interference. And what more helpful link toward acquaintance with other interesting forms of natural life can be found than an intimate friendship with their mutual friends, the trees! The distinctions between trees and shrubs or between shrubs and woody vines are often purely arbitrary, depending in part on age. A plant which grows at least twenty feet tall and usually (not always) has just one woody, self-supporting stem at the ground is considered a tree. A plant which rarely grows taller than twenty feet, in a given region, and usually has more than one woody stem rising from the ground is considered a shrub. The separation of herbs from woody plants divides those plants which usually die down to the ground each winter from those having woody stems which persist above ground year after year. Some ninety different woody plants are distinguished from one another and briefly described in this key and guide. Each description represents a single species with the exception of the cactus, yucca, red oaks and red haws; the differences between the various species of these plants are too complex for this brief manual. Scientific names are included here, not with any thought that they should be memorized or that they need be used in ordinary conversation, but to avoid the possibility of misunderstandings such as often arise from some common names which are used by different persons to designate different plants. Many plants have more than one common name and often one common name is used for two or more quite unlike plants. Common names listed first are the ones considered more suitable. The first part of the scientific name represents the genus (plural, genera), a degree of relationship or grouping smaller than the family but more inclusive than the species. The second name represents the species or specific kind of plant; species are occasionally divided into varieties (var.). The abbreviation following the scientific name stands for the name of the botanist who first described or named the plant, scientifically. L. stands for Linnaeus, “the father of modern botany”, who first used this double-name (binomial) system of scientific classification. More extended descriptions and further information about these plants may be found in some of the reference books listed in the back of this booklet; many, if not all of them, are available in the Dallas Public Library. Only the more necessary technical words have been used and these are defined or illustrated herein. Although this booklet endeavors to include all the woody plants growing naturally in Dallas County, no doubt omissions and errors will be found and the author will be glad to be informed of them.
Das E-Book können Sie in Legimi-Apps oder einer beliebigen App lesen, die das folgende Format unterstützen:
Ähnliche
Norma J. Stillwell
Table of contents
KEY AND GUIDE TO NATIVE TREES, SHRUBS AND WOODY VINES OF DALLAS COUNTY
PREFACE
HOW TO USE THE KEY
GLOSSARY
Leaves Compound and Opposite
CASHEW FAMILY
HONEYSUCKLE FAMILY
BIBLIOGRAPHY
INDEX
Transcriber’s Notes
KEY AND GUIDE TO NATIVE TREES, SHRUBS AND WOODY VINES OF DALLAS COUNTY
by NORMA STILLWELL Dallas, Texas April, 1939
PRINTED BY PROCTOR-ADAMS PRINTING SERVICE DALLAS, TEXAS
PREFACE
This simple key and guide to the woody plants—trees, shrubs and woody vines—which grow naturally in Dallas County, Texas, has been prepared to help beginners of any age in getting better acquainted with these leafy neighbors and friends. Woody plants offer one of the best places to begin a study of nature: first because there are but few kinds to learn in comparison with many other living forms—about 90 of these plants against estimated numbers for the county of about 300 birds, 500 to 1000 other flowering plants and over 25,000 insects; second, woody plants remain in one place, freely available for observation at any hour or season and year after year—if they escape human interference. And what more helpful link toward acquaintance with other interesting forms of natural life can be found than an intimate friendship with their mutual friends, the trees!
The distinctions between trees and shrubs or between shrubs and woody vines are often purely arbitrary, depending in part on age. A plant which grows at least twenty feet tall and usually (not always) has just one woody, self-supporting stem at the ground is considered a tree. A plant which rarely grows taller than twenty feet, in a given region, and usually has more than one woody stem rising from the ground is considered a shrub. The separation of herbs from woody plants divides those plants which usually die down to the ground each winter from those having woody stems which persist above ground year after year. Some ninety different woody plants are distinguished from one another and briefly described in this key and guide. Each description represents a single species with the exception of the cactus, yucca, red oaks and red haws; the differences between the various species of these plants are too complex for this brief manual.
Scientific names are included here, not with any thought that they should be memorized or that they need be used in ordinary conversation, but to avoid the possibility of misunderstandings such as often arise from some common names which are used by different persons to designate different plants. Many plants have more than one common name and often one common name is used for two or more quite unlike plants. Common names listed first are the ones considered more suitable.
The first part of the scientific name represents the genus (plural, genera), a degree of relationship or grouping smaller than the family but more inclusive than the species. The second name represents the species or specific kind of plant; species are occasionally divided into varieties (var.). The abbreviation following the scientific name stands for the name of the botanist who first described or named the plant, scientifically. L. stands for Linnaeus, “the father of modern botany”, who first used this double-name (binomial) system of scientific classification.
More extended descriptions and further information about these plants may be found in some of the reference books listed in the back of this booklet; many, if not all of them, are available in the Dallas Public Library. Only the more necessary technical words have been used and these are defined or illustrated herein. Although this booklet endeavors to include all the woody plants growing naturally in Dallas County, no doubt omissions and errors will be found and the author will be glad to be informed of them.
Grateful acknowledgement is made to Dr. W. M. Longnecker and Dr. E. P. Cheatum of the Department of Biology, Southern Methodist University, and to Dr. B. C. Tharp of the Department of Botany and Bacteriology, University of Texas, for their most helpful suggestions and criticisms. Although this booklet is based upon the field observations of the author and her husband, Jerry E. Stillwell, who assisted her in many ways, she has made free use of such technical information as was needed from the volumes listed in the bibliography.
The illustrations used in this publication were drawn for it by Alice Ferguson.
NORMA STILLWELL,Dallas, Texas.
Copyright 1939 by the author.
HOW TO USE THE KEY
This key is based chiefly on leaves and twigs, as they offer the easiest clues for identification, especially in this climate where leaves are present about three-fourths of the year. The best method of study is to carry this booklet to the woody plant or plants you want to know. If this is not convenient, have at least a leafy twig in hand. When collecting specimens for study (a large-paged magazine will do for carrying and pressing), notes should include the date and location, any peculiarities of the bark, nature of thorns if not on the specimen taken, color of twigs or any other features which might change in drying, flowers or seeds or any such extra clues which might help to find the right name for the plant. Small specimens of leafy twigs may be taken in suitable locations without endangering or damaging woody plants provided they are always cut, never torn from the branches.
The sizes as well as shapes of leaves are usually more typical on older plants or on the higher branches of trees. When either leaves or twigs are described as opposite, this condition will be found to be true for both, although sometimes the opposite member is missing; but leaflets (leaf-like units of a compound leaf) may sometimes be opposite when the complete leaves are not—the position of leaves, not leaflets, is used in this key. The terms rare, common or abundant are used to apply solely to Dallas County.
Begin with the numbers 1 in the key and decide which of these fits the woody plant whose name you are seeking. Turn to the key number following the 1 you have chosen and again choose between the two descriptions bearing the same number. Continue this process until you have reached the name of a plant. This name will be followed by some number above 200; turn to this number in the guide and see whether this more complete description fits. If each of your choices in the key has been correct you now know the name of your plant. If this description in the guide does not fit your plant, go over the key again, selecting this time the other choice at any number where you may have been in doubt.
Whenever it has been necessary to use an obscure or variable characteristic an effort has been made so to arrange the key that the right answer will be reached whichever the choice. That is why some plant names appear more than once in the key. If the following points are noted any careful observer should be successful in identifying the native woody plants of Dallas County by the use of this key. It will be found helpful in other regions where the native plants are similar to those of Dallas County.
1. Look carefully for thorns or prickles.
2. Notice anything unusual about the bark of trunk and branches—knotty, flaky, peeling, color, etc.
3. Try to choose mature leaves of typical shapes and sizes rather than the unusual ones.
4. Look for flowers, fruits or seeds on or under a tree or other woody plant. These may furnish just the confirmation you need to feel sure of the right name.
GLOSSARY
axil: the angle where a leaf stem joins a twig.
deciduous: losing its leaves in winter, not evergreen.
dioecious: bearing staminate, or male, flowers on separate plants from the pistillate, or fruit-bearing flowers; hence some plants of certain species never bear fruits or seeds.
fruit: that part of any plant which contains the seeds.
lenticel: air pore in the bark.
monoecious: bearing the two kinds of flowers on the same plant.
opaque: not admitting or transmitting light.
perfect: having both stamens and pistils in one flower, as most showy flowers have.
pistillate: possessing a pistil or pistils and lacking stamens; female, or fruit-bearing.
staminate: possessing stamens and lacking a pistil; male, or pollen-bearing.
translucent: admitting some light but not clear or transparent.
