Field Botany – Spring 2013
Course Website
Botany Labs
Textbook
How many plant species are there? Illinois – over 3200 vascular plants Northeastern North America – over 4600 vascular plants (Gleason and Cronquist) California – over 4400 vascular plants
From Gleason and Cronquist 1991
How many plant species are there? Illinois – 58,000 square miles – over 3200 vascular plants Costa Rica – 19,600 square miles – over 8,000 vascular plants
How many plant species are there? - total in ,000 Bryophytes (mosses, liverworts and hornworts) 12,000 Pterophytes (ferns and fern allies) 1021 Gymnosperms 282,000 flowering plants (Angiosperms) 311,000 total plant species Some add in green algae – 8500 species
How many endangered plant species? In 1997 the IUCN (International Conservation Union) Red Data list for plants rated 34,000 species as endangered out of 60,000 species evaluated Then changed evaluation procedures – IUCN now rates 8,000 species as endangered out of 11,000 species evaluated UK (very well known flora) lists 20% of species as endangered Likely that 1 out of 4 plant species is endangered
Aceraceae – The Maples
Maple samaras (fruits)
Asteraceae – The Sunflowers, Asters
Annual Sunflower
Goldenrod
Poaceae – The Grasses
Ammophila – Beach grass
Field Trip to Missouri Botanical Garden – April 18
Plant Collection
Taxonomy
Definitions Taxonomy - the study and description of the variation of organisms, the investigation of the causes and consequences of this variation, and the manipulation of the data obtained to produce a system of classification Classification (as process) - the production of a logical system of categories, each containing any number of organisms, which allows easier reference to its components, the kinds of organisms Classification (as object) - is that logical system itself
Definitions cont’d Identification - naming of an organism by reference to an already existing classification system Taxon - any taxonomic grouping - division, class, family, genus, etc. Description - statement of the characteristics of a taxon Characters that contribute to a taxonomic description are known as taxonomic or systematic characters
Definitions cont’d Diagnosis - shortened description covering only those characters (diagnostic characters) which are necessary to distinguish a taxon from other related taxa flora (lower case) - plant life of a given area Flora (upper case) is a book or other work describing the flora of a given area
Classification Need for classification is absolute – it is only by naming organisms and grouping them in recognizable categories that we can begin to understand the vast array of diversity that exists
Southern magnolia – Magnolia grandifolia
RankEndingExample KingdomPlantae Division (Phyla) - phytaMagnoliophyta Class - opsidaMagnoliopsida Order - alesMagnolioales Family - aceaeMagnolioaceae GenusMagnolia Speciesgrandifolia
Star sedge – Carex radiata
RankEndingExample KingdomPlantae Division (Phyla) - phytaMagnoliophyta Class - opsidaLiliopsida Order - alesPoales Family - aceaeCyperaceae GenusCarex Speciesradiata
Hierarchies of plant taxonomy – from Stace