Structures Used to Identify Grasses Source: Penn State Extension Grass Identification Matrix Recommended if you are familiar with grass structures. Common Grasses Found in Pennsylvania Hay and Pasture Fields Life Cycle Grass Inflor- Plant Sheath Blade Collar Auricles Ligule Stem Comments Species escence Height Barnyard grass Found in late summer/ early Round and Annual Over- 1-15mm wide. Flat Panicle of spike- fall. Seed structures purplish Broad None None branching at 1-3 ft lapping with rough edges. like branches. and covered with short stiff Echinochloa nodes. muricata Beauv. bristles. Spreads by both stolons and 3-7 spiked Bermudagrass Perennial/ rhizomes. Found as a 8-15 mm wide. Hairy Prostrate branches Cynodon dactylon Annual Papery Narrow None Fringe of hairs perennial only in very on top and bottom. and upright originating from L. 1-2 ft southern PA and further a single whorl. south. 10-14mm wide. Big Bluestem Stems purplish at base. Awns Perennial Smooth with fringe of Short Round and Raceme, red in Andropogon Split, hairy Narrow None in seed clusters makes inflo- 7-9 ft hairs at junction of membrane upright color. gerardii Vitman rescence look hairy. blade and sheath. Crabgrass 5-12 mm wide. Rough 3-10 spiked Membrane. (Large) Annual Over- edges with hairs on Broad and Upright to branches in Found in late summer/ early None Rounded at Digitaria 2-3 ft lapping both sides. Red- divided prostrate whorls at top of fall. top sanguinalis L. purple color. stem. Crabgrass 5-12mm wide with no 3-10 spiked Membrane. Found in lawns or heavily (Smooth) Annual Over- hairs on either side. Broad and Upright to branches in None Rounded at grazed pastures in late Digitaria 1-2 ft lapping More purplish than divided prostrate whorls at top of top summer/ early fall. ischaemum L. Large Crabgrass stem. Fall panicum 10-20 mm wide. Panicum Annual Over- Upright to Fine, wide- Found in late summer/ early Smooth or sparsely Broad None Fringe of hairs dichotomiflorum 1-4 ft lapping prostrate spreading panicle fall. hairy near base Michx. Common Grasses Found in Pennsylvania Hay and Pasture Fields Life Cycle Grass Inflor- Plant Sheath Blade Collar Auricles Ligule Stem Comments Species escence Height Over- 10-20 mm wide. Inflorescence bushy like a Giant foxtail Annual lapping. Broad and hairy Round and Spike-like panicle, Hairy on top and None Fringe of hairs fox's tail. Hairy blade is key Setaria faberi. 3-6 ft Edges are on edges upright bristly, drooping smooth on bottom. to identification. hairy Over- 5-12 mm wide. Not Broad and Inflorescence bushy like a Green foxtail Annual lapping. Round and Spike-like panicle, hairy on top or sometimes None Fringe of hairs fox's tail and slightly purple Setaria viridis L. 1-3 ft Edges are upright bristly bottom. hairy in color. No hairs on leaves. hairy Italian ryegrass Annual to 2-6 mm wide. Flat Membrane. Bunchgrass with waxy leaves Over- Round-to- Slender stiff spike Lolium italicum Perennial and pointed at tip. May be divided Overlapping Rounded at that are shiny. Spikelet edge lapping flat with awns. Parn. 1-2 ft Waxy. top against stem. Kentucky Sod-grass (short rhizomes) Perennial 2-5 mm wide. Boat- Very short Round-to- bluegrass Split Broad None Fine pannicle dark green. Invades 1-2 ft shaped tip. membrane. flat Poa pratenis L. overgrazed pastures. Nimblewill Split and 2-4 mm wide. Rough Sod-forming (stolons). Perennial Short Mostly Many fine, Muhlenbergia over- on top with hairs Narrow None Flowers in late summer to 1-2 ft membrane prostrate slender panicles. schreberi Gmel. lapping behind ligule. early fall. Orchardgrass 5-12 mm wide. V- White Perennial Broad and Bunchgrass. Light green in Dactylis glomerata Split shaped at base, flat None membrane, Flat Course panicle. 1-3 ft divided color. L. and pointed at tip. pointed at top Short growing bunchgrass Perennial 2-6 mm wide. Folded Perennial Over- Narrow, may Membrane, Round-to- Slender stiff with waxy leaves that are ryegrass in shoot V-shapped, Short 1-2 ft lapping be divided toothed at top flat spike. No awns. shiny. Spikelet placed with Lolium perenne L. Waxy edge against stem. Over- 5-10 mm wide. Sod forming with prominent Quackgrass Perennial Broad and Long- Short lapping Slightly hairy on Round Slender stiff spike fast spreading rhizomes. Elytrigia repens. 1-3 ft divided clasping membrane with hairs upper surface. Spikelet flat against stem. Common Grasses Found in Pennsylvania Hay and Pasture Fields Life Cycle Grass Inflor- Plant Sheath Blade Collar Auricles Ligule Stem Comments Species escence Height Red top Panicle. Rust Sod-grass (short rhizomes). Perennial Over- Broad and V- Agrostis gigantea 2-7 mm wide. Flat. None Tall membrane Round colored at Prominent ridges on upper 1-3 ft lapping shaped. Roth maturity. surface of blade. Reed canarygrass Narrow and Perennial Over- 10-20 mm wide. Flat Prominent Sod forming (prominent Phalaris continuous. None Round Panicle 1-6 ft lapping with rough edges. membrane rhizomes.) arundinacea L. Yellow. Young plants may have Smooth Perennial 4-12 mm wide. Flat Narrow and Short Large panicle, pubescence on sheath. bromegrass Closed None Round 1-3 ft and pointed at tip. divided membrane often drooping Rhizomes covered with Bromus inermis L. brown papery scales. Switchgrass Split, with Perennial 7-14 mm wide. Hairy Broad, often Fringe of short Round and Leaves covered with hairs. Panicum virgatum hairy None Large panicle 3-8 ft on top. with hairs. hairs upright Spreads by rhizomes. L. margin Tall Fescue Broad and 5-10 mm wide. Dark Bunchgrass. Prominently Festuca Perennial Over- divided. Blunt with Short green. Very rough Round Spreading panicle veined, leathery, dark green arundinacea 1-3 ft lapping Wrinkled on few hairs membrane edges leaves with rough edges. Schreb. edges White Timothy Bunchgrass with corms Perennial Over- 4-12 mm wide. Flat Broad and membrane Phleum pretense None Round Spike-like panicle (onion-like bulb at base of 2-3 ft lapping and pointed at tip continuous with two L. stem) notches Witchgrass Leaves covered with hairs. Annual Over- 8-15 mm wide. Hairy Round and Panicum capillare Narrow None Fringe of hairs Large panicle Large panicle often breaking 1-3 ft lapping on top and bottom upright L. off of stem. Inflorescence is bushy like a Over- 5-10 mm wide. Hairy Yellow foxtail Annual Broad and hairy Round and Spike-like panicle, fox's tail. Hairs only on lapping, only on top near base None Fringe of hairs Setaria glauca. 1-3 ft on edges upright bristly upper surface of blade near not hairy of blade. base. Glossary Annual: A plant that completes its life cycle and dies within a year. Awn: A bristle characteristic of the spikelets in some grasses. Bunchgrass: Plant has no stolons or rhizomes and consequently grows in a bunch rather than spreading. Inflorescence: Flower structure of a grass plant. Node: A joint where a leaf is or was attached to a stem. Panicle: A type of flower in which the flower clusters are attached to the stem via branches connected to branches off the stem. Perennial: A plant that lives through three or more seasons. Prostrate: Growing flat along the ground. Raceme: A type of flower in which the flower clusters are attached to the stem via branches. Rhizome: A stem that grows horizontally along the ground surface and may form adventitious roots at the nodes. Sheath: Base portion of the grass leaf that wraps around the stem. Spike: A type of flower in which the flower clusters are attached directly to the stem. Stolon: A stem that grows horizontally along the ground surface and may form adventitious roots and a new plant at the nodes. Barnyardgrass – Flower Barnyardgrass – Whole plant Bermudagrass – Whole plant Barnyardgrass – Stem Bermudagrass – Flower Big Bluestem – Whole plant Bermudagrass – Stolons Big Bluestem – Flower Large Crabgrass – Whole plant Large Crabgrass – Ligule Smooth Crabgrass – Whole plant Smooth Crabgrass – Leaves Fall Panicum – Whole plant Fall Panicum – Ligule Smooth Crabgrass – Flower Fall Panicum – Flower Giant Foxtail – Whole plant Giant Foxtail – Flower Giant foxtail – Plant and flower Italian ryegrass (with clover) – Whole plant Green foxtail – Sheath, collar, and ligule Italian ryegrass – Flower Green foxtail – Flower Kentucky Bluegrass – Ligule Kentucky Bluegrass – Whole plant Kentucky Bluegrass – Leaf Kentucky Bluegrass – Flower Orchardgrass – Whole plant Nimblewill – Whole plant Orchardgrass – Ligule Nimblewill – Flower Orchardgrass – Stem Orchardgrass – Flower Orchardgrass – Collar Perennial Ryegrass – Whole plant Perennial Ryegrass – Flower Perennial Ryegrass – Auricles Perennial Ryegrass – Spikelet Quackgrass – Flower Quackgrass – Plants Quackgrass – Rhizome Red Top – Whole plant Quackgrass - Auricles Red Top – Ligule Reed Canarygrass – Whole plant Red Top – Flower Reed Canarygrass – Leaf Reed Canarygrass – Flower Reed Canarygrass – Ligule Smooth Bromegrass – Whole plant Smooth Bromegrass – Sheaths Smooth Bromegrass – Flower Switchgrass – Whole plant Tall Fescue – Whole plant Tall Fescue – Blade Switchgrass – Flower Tall Fescue – Auricles Timothy – Whole plant Tall Fescue – Flower Timothy – Flower Timothy – Collar Timothy – Corms Witchgrass – Flower Witchgrass – Whole Plant Yellow Foxtail – Whole plant Witchgrass – Sheath Yellow Foxtail – Leaf Blade Yellow Foxtail – Flower .