Monocots, Dicots, Gymnosperms & Ferns Plant Classification & Basic Plant Groups for the Landscape
Classification of Plants Taxonomic classification starts with the least specific – “it’s a plant” And ends with the most specific – “the individual plant by name” Kingdom Division Class Order Family Genus Species
Classification of Plants It all begins with the Plant Kingdom Kingdom Plantae Similarities They all photosynthesize
See Handouts: Classifications of Living Organisms Traditionally Regarded as Plants Plant Morphology: A Summary
Division Division (synonymous with phylum) Suffix –phyta Divided into three (3) groups
Division Seedless, nonvascular plants Bryophyta – the bryophytes Mosses & liverworts
Division Seedless vascular plants Sphenophyta – horsetails Pterophyta – ferns Both used in landscaping
Division Seed bearing vascular plants Cycadophyta – cycads Ginkgophyta – ginkgo or maidenhair Coniferophyta – conifer Gnetophyta – gnetophytes All fall into the group “Gymnosperms” – naked seed
Division Anthophyta – angiosperms Flowering plants Divided into two (2) classes Monocotyledons – monocots Dicotyledons - dicots
Order Groups of related families based on phylogenetic unity (fossil records, comparative anatomy, etc.) Suffix –ales Rosales
Family Grouped by similar genera Similarities in flowering Large families split into tribes Similar tribes split into sub-families Similarities in foliage are NOT reliable for identification Suffix –aceae Rosaceae
Genus Always italicized OR underlined Generic name form First part of Latin binomial naming system Comprises a group of obviously similar species
Genus Usually related by reproductive organs and methods Can be further broken down into sub-genera
species In most cases it’s lowercase, italicized OR underlined In some cases it may be capitalized and in ‘Single Quotes’
species Specific epithet Second part of the Latin binomial naming system Refers to an individual group
species Groups typically do not cross sexually Sexual crosses are usually sterile Sub-species are species separated by environmental factors
Varieties (var.) Usually in ‘single quotes’ Tends to be a variation in the species Typically naturally occurring Maybe only represented by something as simple as foliage color or growth habit
Cultivars (Cv.) Often Capitalized and in ‘Single Quotes’ Cultivated variety produced by horticultural techniques and breeding
Classification of Plants Genus x species x = hybrid cross between two different species Can be naturally occurring or man-made
Classification of Plants x Genus species x = hybrid cross between two different genera Can be naturally occurring or man-made
Horsetails Division Sphenophyta Equisetum is the only genus in the division Scouring rush About 35 species of Equisetum
Horsetails Fossil records Seedless vascular plants Spores not seeds Jointed, tubular stems Stems grooved
Horsetails Rhizomatous Invasive in the landscape
Polystichum mandersonii Ferns Division Pterophyta Primitive plant group Fossil records 12,000 species Seedless vascular plants Spores not seed Sporophytes Rhizomatous, clumping, single stem Ferns Ferns are primitive plants well represented in fossil records There about 12,000 known species Ferns are seedless vascular plants Mature ferns are referred to as a sporophyte They reproduces by spores not seeds About 2/3s of the world’s ferns are found in the tropics, the rest in temperate regions including the deserts Most ferns spread by rhizomes, some are clumping Polystichum mandersonii
Ferns (cont.) Adventitious roots Leaves = fronds Compound pinnate fronds Pinnae on rachis held up by petiole New fronds = “fiddleheads” Ferns (cont.) Adventitious roots develop from the underside of the rhizomes Leaves are referred to as fronds Leaves are usually compound pinnate Leaf pinnae are attached to the rachis and held up by the petiole or stipe New leaves are coiled as they emerge and are referred to as “fiddleheads” Fiddleheads
Ferns (cont.) Homosporus Sori on underside of fronds Sporangia clustered in sori Ferns (cont.) Most ferns are homosporus – they produce only one “type” of spores Sporangia are found on under sides of fronds, on modified fronds, or on separate stalks Sporangia are arranged into groups or clusters called sori, sorus (pl.)
Ferns (cont.) Ferns (cont.) Pteridium sp. Osmunda sp.
Fern Life Cycle Fern Life Cycle
Ferns (cont.) Spores in the sporangium Ferns (cont.) Spores are contained within the sporangium
Ferns (cont.) Indusia covers the sori Ferns (cont.) An indusia covers the sori (indusium sing.)
Ferns (cont.) Meiosis in sporangium Indusium ruptures Sporangium Meiosis occurs in the sporangia When sporangia are ripe the indusium ruptures Indusium
Ferns (cont.) Annulus cells contract Lip cells rupture Spores ejected The annulus cells contract causing lip cells to rupture The spores are ejected through the opening
Ferns (cont.) Spore germinates into filamentous gametophyte Protonema develops into prothallus Ferns (cont.) Spores germinates and develop into young filamentous gametophytes called protonema The protonema develops into prothallus The prothallus is amorphous to heart-shaped with a “notched” end Filamentous Gametophyte
Ferns (cont.) Rhizoids develop Antheridium forms Archegonia forms Free water is necessary Fertilization occurs Zygote forms Ferns (cont.) Rhizoids develop on underside of the prothallus Antheridium containing male sperm cells develop on underside of prothallus usually close to the rhizoids Archegonia containing female egg cells develop on underside of prothallus usually closer to the notched end Free water is required for sperm cells to find egg cells Zygote forms immediately after fertilization
Ferns (cont.) Prothallus used as food source First leaf and roots The new sporophyte Ferns (cont.) As the embryo develops the prothallus is used for the initial food source and eventually dies off The first roots with and leaf form Rhizomes and leaves form as the plant matures to create the new sporophyte generation
Ferns (cont.) Ferns (cont.)
Ferns (cont.) Ferns (cont.)
Gymnosperms Divisions Cycadophyta, Ginkgophyta, Coniferophyta & Gnetophyta “Naked Seeds” Primitive plants Fossil records No flowers About 800 species Gymnosperms Divisions Cycadophyta, Ginkgophyta, Coniferophyta and Gnetophyta Gymnosperm literally means “Naked seeds” Gymnosperms are primitive plants well represented in fossil records Gymnosperms do not bear flowers
Gymnosperms (cont.) Up to 15 cotyledons No endosperm Food stored in female (1n) gametophyte tissue in seed Gymnosperms (cont.) Seedlings can have up to 15 cotyledons The seed has no endosperm - food storage is contained in the female haploid gametophyte tissue in the seed
Gymnosperms (cont.) Woody cones or leathery berries The seeds are developed in a woody cone or leathery “berry-like” structures – they are not developed within an ovary or fruit
Gymnosperms (cont.) Gymnosperms (cont.)
Gymnosperms (cont.) “Leaves” have one or two vascular bundles No cambium in foliage Gymnosperms (cont.) Leaves have one or two vascular bundles of xylem and phloem There is no cambium in or around the vascular system in the leaves
Gymnosperms (cont.) Woody and branching Root system also woody and branching Wind pollinated Vascular tissue in stems in discrete rings Gymnosperms (cont.) Gymnosperms are typically woody, branching plants with exception of the Cycads Gymnosperms also have a woody, branching root system Most gymnosperms are passively pollinated or wind pollinated The vascular tissue xylem, phloem and cambium are in discrete vascular rings
See Handouts: Principles of Horticulture: Plant Structures and Pruning by G.B. Smith
Gymnosperms (cont.) Needles Needle-like Overlapping scales Fused overlapping scales Pines in fascicles Gymnosperms (cont.) Leaves are needles, needle-like, overlapping scales, or fused overlapping scales
Cycadophyta Gymnosperms (cont.) Cycadophyta The Cycads Cycas sp.
Ginkgophyta Gymnosperms (cont.) Ginkgophyta Ginkgo biloba The only member of the order
Coniferophyta Gymnosperms (cont.) Coniferophyta Conifers Cone-bearing plants Pines Cypress Cedars Podocarpus Etc., etc., etc…..
Gnetophyta Gymnosperms (cont.) Gnetophyta Gnetophytes Ephedra Gnetum Welwitschia
Welwitschia Welwitschia
Welwitschia
Ephedra Ephedra
Gnetum Gnetum
The Flowering Plants Division Anthophyta Angiosperms Flowering plants Angiosperms divided into two groups Monocotyledones – the monocots Dicotyledones – the dicots The Flowering Plants Division Anthophyta The general term for the flowering plants are the Angiosperms The angiosperms are divided into two groups
Monocots vs. Dicots About 235,000 species of flowering plants About 170,000 species of dicots About 65,000 species of monocots Monocots vs. Dicots There are over 235,000 species of angiosperms (flowering plants) About 170,000 species of dicots and about 65,000 species of monocots
Flower Parts Monocot flower parts in 3s The Flowering Plants (cont.) Monocots have flower parts (sepals, petals and anthers) in multiples of 3’s
Flower Parts Dicot parts in 4s and 5s The Flowering Plants (cont.) Dicots have flower parts (sepals, petals and anthers) in multiples of 4’s and 5’s
Flower Parts
See Handouts: The Flower Summary Overall Flower Morphology
Flower Morphology Morphology refers to shape a : branch of biology that deals with the form and structure of animals and plants b : the form and structure of an organism or any of its parts Merriam Webster online dictionary
Flower Morphology Stigma, style and ovary Collectively referred to as the pistil Female parts of the flower
Flower Morphology Anther and filament Collectively referred to as the stamen Pollen occurs on the anther Male parts of the flower
Flower Morphology Petals – modified leaves Often large and scented in insect pollenated plants Small and dull in wind pollinated plants Corolla – the collective term for flower petals
Flower Morphology Not all flowers have separate petals Hence the term corolla
Flower Morphology Sepals – modified leaves Some green, some colored Calyx – the collective term for sepals
Flower Morphology Monoecious both sexes occurring on the same plant . . . in separate male and female flowers
Flower Morphology Dioecious sexes occurring in separate plants in separate male and female flowers
Flower Morphology Hermaphrodite (bisexual) both sexes occur in same flower
Flower Morphology Complete flowers Incomplete flowers contains all four main flower parts corolla, calyx, pistil & stamen Incomplete flowers missing any one or more of the four parts
Flower Morphology Perfect flowers Imperfect flowers contains both pistil and stamen in the same flower Imperfect flowers missing either pistil or stamen
Symmetry Bilateral symmetry Right mirrors left Top does not mirror bottom Pelargonium peltatum Ivy Geranium
Symmetry Radial symmetry Right mirrors left Top mirrors bottom Malus sp. Crabapple
Seeds Monocot Seeds have endosperm for food storage Flowering Plants (cont.) Flower Parts Seeds Monocot seeds rely on endosperm as food storage for the dormant and developing seed
Seeds Dicots use cotyledons for food stores Flowering Plants (cont.) Flower Parts Seeds Dicots rely on stored energy in the cotyledons
Cotyledons Monocots have a single cotyledon The Flowering Plants Flower Parts Cotyledons Monocots have a single cotyledon or primary leaf
Cotyledons Dicots have a pair of cotyledons The Flowering Plants Flower Parts Cotyledons Dicots have a pair of cotyledons that are often used for food storage
Cotyledons The Flowering Plants Flower Parts Cotyledons Dicot vs. Monocot comparison
The Vascular System Monocots have random vascular bundles The Flowering Plants The Vascular System Monocot’s vascular systems consist of random vascular bundles of xylem and phloem Monocots are not “woody” the may appear “wood-like” as in palms
The Vascular System Dicots have discrete vascular rings The Flowering Plants The Vascular System Dicot’s vascular consists of a discrete system of vascular rings of xylem and phloem Dicots can be herbaceous but are most often woody
Above the Ground Monocots are non-woody They tend to be leafy The Flowering Plants Above the Ground Monocots do not have a woody-branching above ground system Monocots appearance: Grass-like Long sword-like leaves
Above the Ground Dicots are woody and branching The Flowering Plants Most dicots are woody and branching Some are herbaceous
The Leaves Monocots have parallel venation The Flowering Plants Monocots typically have narrow strap-like leaves Monocots have parallel venation
The Leaves More parallel venation
The Leaves Monocot leaves tatter in the wind
The Leaves Dicots have netted venation The Flowering Plants The Leaves Dicots have leaves in many forms They have a “netted” vein pattern
The Root System Monocots have a fibrous root system The Flowering Plants Below the Ground The Root System The monocot root system is non-branching and fibrous – like a mop head The roots are typically defined as “adventitious”
The Root System Dicots have a woody, branching root system The Flowering Plants Below the Ground The Root System The dicot root system is woody and branching