Introduction to Grasses

Candice Prince, UF/IFAS Center for Aquatic and Invasive Graminoids = “grass like” plants

1. Grasses () 2. Sedges (Juncaceae) 3. Rushes (Cyperaceae) Graminoids = “grass like” plants

1. Grasses (Poaceae) 2. Sedges (Juncaceae) 3. Rushes (Cyperaceae)

Sedges have edges, rushes are round, grasses have joints all the way to the ground Sedges Rushes Grasses

• Triangular stems • Round stems • Round to ellipsoid • Nodes not jointed • Nodes not jointed • Nodes are jointed • Solid stems (not hollow) • Solid stems (not hollow) • Stems usually hollow

Images: Hilton Pond Center Sedges Rushes Grasses

Illinois Wildflowers

• 3-ranked leaves • 3-ranked leaves • 2-ranked leaves • Leaves flat or channeled, • Leaves round, reduced, or flat • Leaves flat, channeled, or round sometimes reduced Sedges Rushes Grasses

Max Licher

• Inflorescence subtended • Inflorescence subtended by bracts • Inflorescence not subtended by bracts by bracts (usually prominent) (not prominent) Sedges Rushes Grasses

Backyard Nature

• Achenes (single seeded hard • Many-seeded capsule • Caryopsis (grain) fruit) Florida Grasses

• ~450 species in FL

• Found in every community type, wide range of conditions • Fire • Wetlands/flooding • Brackish conditions • Xeric conditions Graves Lovell, Bugwood.org

Forest and Kim Starr, Bugwood.org Kaitlyn Quincy, UF/IFAS How to Identify Grasses? Questions to ask: •What is the overall appearance? What is the overall appearance?

•Is it a bunch (caespitose) or creeping grass?

Rebekah D. Wallace, Bugwood.org Jeff D. Hansen What is the overall appearance?

•If creeping: rhizomes, stolons, both? What is the overall appearance?

•Height? Color?

Kevin Hudson, MSU Ag Communications

Walters Gardens What is the overall appearance?

•What are the culms (stems) like? • Color? Node Internode • Smooth? Ribbed?

• Hairy nodes? Node Questions to ask: •What is the overall appearance?

•What are the leaves and sheath like? What are the leaves and sheaths like? •What is the texture? Blade •Smooth? (Lamina) •Hairy? Midrib •Waxy?

•Are the margins sharp?

Margin •Are the veins or midrib prominent?

•Are the leaves flat? V-shaped?

Chris Evans, Bugwood.org What are the leaves and sheaths like? •What is the texture? •Smooth? •Hairy? •Waxy?

•Are the margins sharp?

•Are the veins or midrib prominent?

•Are the leaves flat? V-shaped?

University of Nebraska-Lincoln What are the leaves and sheaths like?

Blade

Midrib

Margin

Arthur Haines

Penn State Extension Questions to ask: •What is the overall appearance?

•What are the leaves and sheath like?

•What is the collar region like? What is the collar region like?

Iowa State University

Oregon State University What is the collar region like?

Penn State Extension

Oregon State University What is the collar region like?

•Does it have a ligule?

•Size of the ligule?

•Is the ligule a membrane? Hairy?

Oregon State University Peter Smith •Does it have auricles?

Penn State Extension

NC State Extension

Amy Ferriter, Bugwood.org Questions to ask: •What is the overall appearance?

•What are the leaves and sheath like?

•What is the collar region like?

•What type of inflorescence or seed head (if present)? Grass Inflorescence • Floret = grass flowers

• Spikelet = one to several florets • Basic unit of inflorescence

Aelwyn Image: E-Monocot Grass Inflorescence • Each spikelet held in pair of glumes

• Glumes may or may not have awns (bristles)

Aelwyn Grass Inflorescence • Floret: stamen and pistil enclosed by two bracts (lemma and palea) • May or may not have awns • May or may not have hairs • Pay attention to color

Image: John K. Saichuk, LSU Image: E-Monocot What type of inflorescence? • Spike, raceme, or panicle?

EM Armstrong What type of inflorescence? • Spike: unbranched, sessile (spikelets attached directly, no stalks)

EM Armstrong What type of inflorescence? • Raceme: unbranched, spikelets attached by pedicels (stalks)

EM Armstrong What type of inflorescence? • Panicle: branched, spikelets on pedicels

EM Armstrong What type of inflorescence? • Some panicles are compact, appear spike-like Recap (Poll Question)

• A branched inflorescence with spikelets on pedicels (stalks) is called what? • A: panicle • B: spike • C: ligule • D: auricles Recap (Poll Question)

• A branched inflorescence with spikelets on pedicels (stalks) is called what? • A: panicle • B: spike • C: ligule • D: auricles Species Identification Wetland Grasses

• Panicum repens (torpedograss) – exotic • Hymenachne amplexicaulis (West Indian marshgrass) – exotic • Urochloa mutica (paragrass) – exotic • Panicum hemitomon (maidencane) – native Panicum repens (torpedograss)

Forest and Kim Starr, Bugwood.org P. repens – overall appearance

• Spreads via rhizomes and stolons

• Up to 3 ft. in height Rebekah D. Wallace, Bugwood.org

• Hollow stems

• Blue-grey color

Ann Murray, Bugwood.org Forest and Kim Starr, Bugwood.org P. repens – leaves, sheaths, ligule

•Stiff and folded

•Leaves and sheaths hairy

•Ligule hairy

John D. Byrd, Bugwood.org P. repens – inflorescence

•Loose, open panicle

Ann Murray, Bugwood.org

Harry Rose Hymenachne amplexicaulis – West Indian Marshgrass

Far North Coast City Council H. amplexicaulis - overall appearance

• Spreads via stolons and seeds

• 3-8 ft. in height

• Stems filled with white pith H. amplexicaulis – leaves, sheath, ligule

• Hairs near base

• Ligule a small membrane

• Auricles wrap around culm

Far North Coast City Council H. amplexicaulis - inflorescence

• Spike-like panicle Urochloa mutica (paragrass) U. mutica - overall appearance

• Spreads via stolons (seed germination low)

Rebekah D. Wallace, Bugwood.org • 3 ft. in height

Sheldon Navie • Hollow stems

• Swollen hairy nodes

Ann Murray, Bugwood.org Forest and Kim Starr, Bugwood.org U. mutica - leaves, sheath, ligule

• Short hairs on leaves and sheaths

• Ligule is a hairy membrane Rebekah D. Wallace, Bugwood.org

Harry Rose

Sheldon Navie

Forest and Kim Starr, Bugwood.org U. mutca - inflorescence

• Pyramidal panicle

• Often purple-tinged Panicum hemitomon (maidencane) P. hemitomon – overall appearance

•Rhizomatous

•Hollow culms

•May lean and root at nodes P. hemitomon – leaves, sheath, ligule

•Leaves and sheaths smooth to sparsely hairy

•Ligule is ciliate

Southeastern Flora

Larry Allain, US Geological Survey

Larry Allain, US Geological Survey Larry Allain, US Geological Survey P. hemitomon – inflorescence

•Spike-like panicle Cane Grasses – tall, with cane-like stems

Jennifer Possley

James H. Miller, Leslie J. Mehrhoff, Bugwood.org Bugwood.org Cane grasses

• (common reed) – native and exotic forms • (giant reed) – exotic • reynaudiana (Burma reed) – exotic Phragmites australis (common reed) P. australis – overall appearance

• Up to 20 ft. tall

• Spreads through rhizomes, stolons, and seeds P. australis – leaves, sheath, ligule

• Leaves have sharp margins

• Ligule is a fringe of hairs Larry Allain, US Geological Survey

P. australis – inflorescence Joseph DiTomaso, Bugwood.org

• Large panicle

• Awns on upper florets

• Silky hairs at maturity

Minnesota Wildflowers Phragmites haplotypes

Eurasian Haplotype Gulf Coast Haplotype Inflorescence Compact, erect Open, drooping Stem Ribbed Smooth Height 6.5 to 13 ft. Up to 20 ft. Arundo donax (giant reed) A. donax – overall appearance

• To 20 ft. tall • Forms clumps • Spreads via rhizomes, stem fragments

Joseph M. DiTomaso, Bugwood.org

John Ruter, Bugwood.org A. donax – leaves, sheath, ligule

• Light brown collar and auricle Amy Ferriter, Bugwood.org

• Sharp margins

• Hairy ligule

Harry Rose Larry Allain, US Geological Survey

A. donax – inflorescence Rebekah D. Wallace, Bugwood.org

• Plume-like, compact panicle

• Upright

• Spikelets have awns

Jim Conrad Burma Reed (Neyraudia reynaudiana)

GlobalSpecies.org Overall Appearance

•Spreads via wind-dispersed seeds and rhizomes •Clumping, to 10 ft. in height •Stems are filled with pith, often branched

Dan Clark, Bugwood.org Leaves

•Blades to 39 in. long, hairy on top •Ligule and collar have hairs Inflorescence

•Large panicles (to 24 in. in length) •Feathery appearance •Silver hairs

Dan Clark, Bugwood.org Upland Grasses

• Imperata cylindrica (cogongrass) – exotic • Melinis repens (natal grass) – exotic Cogongrass (Imperata cylindrica)

Photo: Chris Evans, Bugwood.org Photo: Chris Evans, Bugwood.org Overall Appearance

• Spreads via rhizomes and seeds • May reach 6+ ft. • No aboveground stems, leaves arise directly from rhizomes

Chris Evans, Bugwood.org Overall Appearance

•Rhizomes: •Scales •Sharp-pointed tips

Rebekah D. Wallace, Bugwood.org

Chris Evans, Bugwood.org Leaves Chris Evans, Bugwood.org

•Off-center white midrib •May be hairy at base •Rough edges Leaves Chris Evans, Bugwood.org

•Sheaths are short •Ligule is a fringed membrane Inflorescence •Dense panicle •White/silver •Plume-like •Up to 8 in. long

Chris Evans, Bugwood.org

Chris Evans, Bugwood.org Julia Scher, Bugwood.org Natal Grass (Melinis repens) Overall Appearance

•Spreads via seed

•Grows in clumps to 4 ft. in height

•Bunch grass Leaves

• To 1 ft. in length, upper surface slightly rough

• Sheaths glabrous, may have long hairs

• Ligule: short hairs Inflorescence

• Panicle, to 8 inches long • Pink to purple, hairs turn silver with maturity • Spikelets with long hairs

Forest and Kim Starr, Bugwood.org Thank you!

Candice Prince [email protected]