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