Introduction to Grasses, Sedges GOALS and Rushes • Understand basic plant taxonomy • Learn common terms for plant descriptions • Learn use of plant keys • Differentiate grass/sedge/rush families © Steve D. © Steve Eggers • Sight recognize some common sedges, grasses and rushes • Become familiar with botanical texts © Steve D. Eggers By Steve Eggers June 2015 TAXONOMY EXAMPLE • FAMILY: Poaceae (Grass Family) • FAMILY (e.g., Aster, Sedge, Rose, Grass) • GENUS: Poa (the bluegrasses) • GENUS (always italicize) • SPECIES: pratensis (Kentucky bluegrass) • SPECIES (always italicize) -- Subspecies (Speckled alder: Alnus incana ssp. rugosa) -- Variety (Red raspberry: Rubus idaeus var. strigosus) Poa pratensis SYNONYMS TAXONOMY BOTANICAL TERMS BOTANICAL TERMS • Inflorescence: the entire flower structure including • Glabrous: smooth subtending bracts (modified leaves) • Glaucous: covered with a pale, waxy coating • Annual: a plant that completes its life cycle in one growing • Pubescent: hairy season and then dies • Scabrous: rough • Biennial: a plant that completes it life cycle in two years, • Pistil: the seed producing organ of a flower, composed of an usually flowering and producing fruit the second year, and ovary and one or more styles and stigmas then dies • Ovary: the lower, often enlarged portion of the pistil in which • Perennial: a plant species living 3 or more years the seeds are produced • Rhizome: an underground, usually horizontal, stem • Pistillate: having only pistils (seed producing) • Stolon: an above-ground, usually horizontal, stem • Staminate: having only stamens (pollen producing) BOTANICAL TERMS Sedges vs. Grasses vs. Rushes • Sedges: Solid, triangular stems (“sedges have edges”) with some exceptions; leaves 3-ranked; fruit a nutlet subtended by a scale • Grasses: Hollow (between the nodes), round stems; leaves 2- ranked; fruit a grain covered by two papery scales • Rushes: Solid, round stems; leaves few; fruit a several to many-seeded capsule surrounded by 6 scale-like structures © Steve D. Eggers (tepals) Rhizomes Stem Cross Sections BOTANICAL TERMS: RUSHES (Juncus) • Capsule: fruit of rushes; contains three to dozens of seeds; in Juncus the seeds are tiny, barely visible with unaided eye • Tepals: the six, star-like scales that surround the capsule Illustrations from Wetland Plants and Plant Communities of Minnesota and Wisconsin, Version 3.1 by Eggers and Reed (2014) BOTANICAL TERMS: RUSHES RUSHES • Two major breaks in the keys: -- Is inflorescence terminal or lateral? -- Do leaves have hard cross-partitions? Path rush Soft rush © Steve D. Eggers Terminal Illustration from A Manual of Aquatic Plants by Fassett (1957) Lateral © Steve © Steve D. Eggers BOTANICAL TERMS: GRASSES GRASS SPIKELET/FLORETS • Floret: the highly reduced flower of grasses • Spikelet: a small spike with reduced flowers on a central axis • Pedicel: the stalk of the spikelet • Glumes: the sterile, scale-like leaves at the base of a grass spikelet Floret • Lemmas: the lowermost, scale-like leaves at the base of a grass floret • Ligule: in grasses, a papery, hairy or membrane-like extension at the summit of a leaf sheath Illustration from Wetland Plants and Plant Communities of Minnesota and Wisconsin, Version 3.1 by Eggers and Reed (2014) BOTANICAL TERMS: GRASSES LIGULES • One-flowered spikelets © Steve D. Eggers Steve D. Eggers © © Steve © Steve D. Eggers • Spikelets more than one-flowered © Steve D. Eggers Reed Canary Grass Quack Grass Fowl Blue Grass Illustrations from Manual of the Grasses of the United States by Hitchcock (1950) and Grasses of Iowa drawn by Froeschner (1966) Grass Exercise 1. Stamens and pistils in different spikelets © Steve D. Eggers Pistillate Flowers Wild Rice (Zizania palustris) Staminate Flowers OBL 1. Stamens and pistils in the same spikelet…..2 © Steve D. Eggers 2. Plants 2-4 m. tall with pennant-like leaves, 3. Spikelet covered with many little spines… inflorescence feathery…. © Steve D. Eggers Common Reed by Hitchcock (1950) (Phragmites australis) FACW Wild Millet (Echinochloa crus-galli) FAC (NC/NE); FACW (MW) States United the of Grasses the of Manual Illustration from Illustration from Manual of the Grasses of the United States by Hitchcock (1950) 2. Plants smaller, inflorescence not feathery…………………………………..3 3. Spikelets without numerous spines...4 4. Spikelets all on one side (like a comb)……… © Steve D. Eggers 5. Spikelets made up of several florets….6 © Steve D. Eggers Prairie Cord-Grass 5 Florets (Spartina pectinata) FACW Glumes Illustration from Grasses of Iowa drawn by Froeschner (1966) 5. Spikelets 1-flowered…………………….7 4. Spikelets not all on one side………..………..5 Illustration from Manual of the Grasses of the United States by Hitchcock (1950) 6. Lemmas deeply corrugated (nerved), lemma not 6. con’t: …lemma cottony at base, leaf tips end in boat- cottony at base, leaf tips do not end in boat-shaped shaped tip, spikelets are flattened…….. tip, spikelets not flattened ….. Manna Grasses (Glyceria spp.) © Steve D. Eggers D. © Steve Eggers Illustration from Grasses of Iowa drawn by Froeschner (1966) Bluegrasses (Poa spp.) Floret 6. Lemmas not corrugated,………(next slide) Cottony hairs at base of lemma Illustrations from Manual of the Grasses of the United States by Hitchcock (1950) One flowered spikelets……… 8. Spikelets in close, irregular masses……… 7. Spikelets with fringed margins, © Steve D. Eggers overlapping in a row………. Reed Canary Grass (Phalaris arundinacea) FACW Rice Cut-Grass (Leersia oryzoides) Ligule OBL 7. Spikelets not as above………………………….8 8. Spikelets in loose, open arrangement……….9 9. Lemma surrounded by a tuft of straight, silky Redtop (Agrostis gigantea) FACW © Steve D. Eggers hairs…………………. Canada blue-joint grass (Calamagrostis © Steve D. Eggers (Calamagrosits canadensis) OBL © Steve D. Eggers Single flowered 9. Lemma without hairs…… spikelet, no hairs ……………..Redtop (next slide) Illustrations from Manual of the Grasses of the United States by Hitchcock (1950) SEDGE FAMILY BOTANICAL TERMS: SEDGE FAMILY © Steve D. © Steve Eggers • Spikelet: a small spike with reduced flowers on a central axis • Perigynium: the papery, flask-like structure that surrounds the ovary; unique to the genus Carex Spike-rushes © Steve D. © Steve Eggers • Sedges Achene or nutlet: a small, hard fruit that does not split open along a seam Cottongrasses • Scale: a highly reduced leaf subtending the Sedges flower Spikelets © Steve D. © Steve Eggers Flat-sedges Perigynium Bulrushes © Steve D. Eggers D. Steve © Eggers © Steve D. © Steve Eggers SEDGE FAMILY: Bulrushes SEDGE FAMILY: Bulrush Stem Cross Sections (Schoenoplectus and Scirpus) Softstem Bulrush Hardstem Bulrush (Schoenoplectus acutus) Three-Square Bulrush (Schoenoplectus tabernaemontani) (Schoenoplectus pungens) River Bulrush (Schoenoplectus fluviatilis) Softstem vs. Hardstem Bulrush (Schoenoplectus tabernaemontani) vs. S. acutus) SEDGE FAMILY: Spike-Rushes SEDGE FAMILY: Cottongrasses (Eleocharis) (Eriophorum) Nutlets have many, long, silky bristles Nutlet has a “cap” (tubercle) Blunt Spike-Rush (Eleocharis obtusa) Narrow-leaved Cottongrass (Eriophorum angustifolium) SEDGE FAMILY: Flat-Sedges (Cyperus) SEDGE FAMILY: Sedges (Carex) Pistillate Pistillate Staminate Spikelet Spikelets are flattened Spikelet (circled) has both (2-sided) pistillate and staminate flowers Also called nutgrasses Staminate Spikelet © Steve D. Eggers © Steve D. Eggers Carex: Perigynium Carex: Flower Structure Perigynia = peri (around) + gynia (gynoecium, female portion of flower) Sedge pistils with 2 carpels produce lens- shaped nutlets (lenticular) Sedge pistils with 3 carpels produce triangular- shaped nutlets (trigonous) Illustration from Wetland Plants and Plant Communities of Minnesota and Wisconsin, Version 3.1 by Eggers and Reed (2014) No Yes Are nutlets enclosed in sacs (perigynia)? Carex Carex: Perigynium No Are spikelets flattened and scales of spikelet 2-ranked? Yes No Yes Teeth Dulichium Are flowers terminal rather than axillary? Cyperus Beak No Are spikelets one- or two-flowered rather than +++ flowered? Yes Rhynchospora Are nutlets crowned with persistent tubercles and do stems Yes Nerve No lack leaves? Eleocharis Body Are nutlets subtended by a few (1-8) short bristles rather than many long bristles? No Yes Eriophorum Scirpus Schoenoplectus Modified from S. Galatowitsch, U of MN, 1994 Illustrations from Wetland Plants and Plant Communities of Minnesota and Wisconsin, Version 3.1 by Eggers and Reed (2014) Common Sedges Common Sedges BLADDER SEDGE (Carex intumescens) BOG SEDGE FACW (Carex oligosperma) OBL • Leaves wiry, less than 3 mm. wide • Forms extensive stands • Unmistakable • Very large (bladder-like) perigynia © Steve D. Eggers (Page 258) (Page 355) [Page numbers refer to Wetland Plants and Plant Communities of MN and WI, Version 3.1 by Eggers and Reed (2014)]. Common Sedges Common Sedges TUSSOCK SEDGE © Steve D. Eggers LAKE SEDGE (Carex stricta) © Steve D. Eggers (Carex lacustris) OBL OBL • Does not form tussocks • • Forms tussocks W-shaped leaf shape • • W-shaped leaf shape Base reddened, has pinnate fibers • • Base reddened, has pinnate fibers Stem diameter larger than a pencil • Stem diameter smaller than a pencil © Steve D. Eggers © Steve D. Eggers © Steve D. Eggers (Pages 112-113) (Pages 138-139) Common Sedges Common Sedges FOX SEDGE WOOLY SEDGE (Carex vulpinoidea) (Carex pellita) OBL OBL • “Foxtail” inflorescence • Leaf sheaths with cross wrinkles • Stems hard, stiff • Perigynia pubescent (e.g., woolly) • Leaves flat, greater than 2.5 mm. wide • Very common,