POACEAE [GRAMINEAE] – GRASS FAMILY Plant: annuals or perennials Stem: jointed stem is termed a culm – internodial stem most often hollow but always solid at node, mostly round, some with stolons (creeping stem) or rhizomes (underground stem) Root: usually fibrous, often very abundant and dense Leaves: mostly linear, sessile, parallel veins, in 2 ranks (vertical rows), leaf sheath usually open or split and often overlapping, but may be closed Flowers: small in 2 rows forming a spikelet (1 to several flowers), may be 1 to many spikelets with pedicels or sessile to stem; each flower within a spikelet is between an outer limna (bract, with a midrib) and an inner palea (bract, 2-nerved or keeled usually) – these 3 parts together make the floret – the 2 bottom bracts of the spikelet do not have flowers and are termed glumes (may be reduced or absent), the rachilla is the axis that hold the florets; sepals and petals absent; 1-6 but often 3 stamens; 1 pistil, 1-3 but usually 2 styles, ovary superior, 1 ovule – there are exceptions to most everything!! Fruit: seed-like grain (seed usually fused to the pericarp (ovary wall) or not) Other: very large and important family; Monocotyledons Group Genera: 600+ genera; locally many genera 2 slides per species WARNING – family descriptions are only a layman’s guide and should not be used as definitive TRIBE PANICEAE - annual or perennial - cespitose or not, rhizomes or not - culms annual, not woody, branched or unbranched, small to several meters - ligules rarely absent, membranous (often ciliate) and/or hairy but rarely absent - leaves basal and/or cauline; leaf sheaths mostly open - inflorescence an open or somewhat dense panicle (often terminal, sometimes axillary or subterranean) or spike-like panicle or a secund (on one side) spike or raceme- like with paired or alternate spikelets - spikelet often flattened next to axis and rounded dorsally but varies - with 1 (rarely 2) lower sterile, staminate or reduced floret(s) and an upper fertile floret - disarticulation usually below the glumes (rarely above or at nodes of axis) - lower glume small (usually < ½ length of spikelet) or absent, upper glume similar in length to upper floret, herbaceous or papery (thin and membranous), rarely absent - lower lemma(s) similar to upper glume, upper lemma hardened (or leathery) and thick - paleas with 2 nerves (sometimes faint), fertile floret palea similar to fertile lemma - usually 3 stamens - stigmas often red - caryopses terete or dorsally compressed WARNING – tribe descriptions are only a layman’s guide and should not be used as definitive POACEAE [GRAMINEAE] – PANICEAE TRIBE Field [Mat] Sandbur; Cenchrus longispinus (Hack.) Fernald - Paniceae (Tribe) Dune Sandbur; Cenchrus tribuloides L. - Paniceae (Tribe) Tapered Rosette Grass; Dichanthelium acuminatum (Sw.) Gould & C.A. Clark var. acuminatum – Paniceae (Tribe) Bosc's Panicgrass; Dichanthelium boscii (Poir.) Gould & C.A. Clark – Paniceae (Tribe) Starved Panicgrass; Dichanthelium depauperatum (Muhl.) Gould Broadleaf Rosette Grass; Dichanthelium latifolium (L.) Gould & C.A. Clark Openflower Rosette Grass; Dichanthelium laxiflorum (Lam.) Gould – Paniceae (Tribe) Southern Crabgrass; Digitaria ciliaris (Retz.) Koeler - Paniceae (Tribe) Barnyard Grass; Echinochloa crus-galli (L.) P. Beauv. (Introduced) - Paniceae (Tribe) Rough Barnyard Grass; Echinochloa muricata (P. Beauv.) Fernald - Paniceae (Tribe) Beaked Panicgrass; Panicum anceps Michx. - Paniceae (Tribe) [Common] Witchgrass; Panicum capillare L. - Paniceae (Tribe) Switchgrass; Panicum virgatum L. - Paniceae (Tribe) Florida Paspalum; Paspalum floridanum Michx. - Paniceae (Tribe) Field paspalum; Paspalum laeve Michx. - Paniceae (Tribe) Thin Paspalum; Paspalum setaceum Michx. - Paniceae (Tribe) Marsh Bristle grass [Knotroot Foxtail]; Setaria parviflora (Poir.) Kerguélen - Paniceae (Tribe) Green Bristlegrass [Foxtail]; Setaria viridis (L.) P. Beauv. (Introduced) - Paniceae (Tribe) Species with one page are under revision Field [Mat] Sandbur - p1 USDA Cenchrus longispinus (Hack.) Fernald Poaceae (Grass Family); Paniceae (Tribe) Oak Openings Metropark, Lucas County, Ohio Notes: Plant annual, mostly erect to decumbent, to 80+ cm; Culm terete, often branching near base; Roots fibrous, without rhizomes; Leaf Blades up to 1 to 1.5 cm wide, to 30-40 cm long, glabrous or somewhat hairy; Ligules membranous; Inflorescence a panicle (spike-like) to 10+ cm, usually 4 to 18+ clusters of spikelets, these clusters of 1 to 4 (usually 2-3) spikelets form burs with bristles and flattened base spines, each spikelet with 1 sterile and 1 perfect floret; many habitats, especially sandy areas, burs cause a painful nuisance; late spring to fall [V Max Brown, 2013] Bur – sometimes Field [Mat] Sandbur – p2 referred to as a Cenchrus longispinus (Hack.) Fernald Fascicle (cluster or [V Max Brown, 2013] bundle - in this case enclosing spikelets ) Spikelet Upper series of upward pointed spines Lower, downward pointing series of spines Bur and Spikelet Dune Sandbur - p1 USDA Cenchrus tribuloides L. Poaceae (Grass Family); Paniceae (Tribe) Tybee Island, Georgia Notes: Plant annual, mostly decumbent to erect, to 70+ cm; Culm terete, often branching and rooting at nodes near base; Roots fibrous, without rhizomes; Leaf Blades up to 1 to 1.5 cm wide, to 30-40 cm long, glabrous or somewhat hairy; leaf sheath glabrous to hairy; Ligules small and membranous; Inflorescence a panicle (spike-like) to 8+ cm, clusters of 1 to 2 spikelets form densely hairy burs (up to 1.5 cm) with bristles and flattened base spines, each spikelet with 1 sterile and 1 perfect floret; painful nuisance on Atlantic and some gulf beaches; late spring to fall [V Max Brown, 2013] Dune Sandbur – p2 Cenchrus tribuloides L. [V Max Brown, 2013] Burs densely hairy Tapered Rosette Grass – p1 USDA Dichanthelium acuminatum (Sw.) Gould & C.A. Clark var. acuminatum Poaceae (Grass Family); Paniceae (Tribe) Wire Road Conservation Area, Stone County, Missouri Notes: Plant perennial, erect, to 70+ cm, some clumping; Culm terete, hairy in this variety; Roots fibrous; basal leaves shorter and broader than cauline leaves; Leaf blades up to 12+ cm long, usually less than 10 mm wide; Leaf Sheaths hairy including on margins usually; Ligules of hair up to 5 mm; Inflorescence a panicle up to 10 cm, branches mostly spreading and rebranching; spikelets 1 to 2+ mm long, Glumes present, lower glume much shorter than upper, upper glume almost as long as spikelet; 2 florets, lower floret usually sterile, upper floret perfect (see photos); many habitats; late spring to early fall [V Max Brown, 2014] Ligule of hairs up to 5 mm Basal leaves shorter and broader than stem leaves Tapered Rosette Grass – p2 Dichanthelium acuminatum (Sw.) Gould & C.A. Clark var. acuminatum [V Max Brown, 2014] 1.5 mm Anthers and style from fertile floret Upper fertile Floret Lower Lemma upper Glume Lower Glume Lower Lemma upper Glume Bosc's Panicgrass – p1 USDA Dichanthelium boscii (Poir.) Gould & C.A. Clark Poaceae (Grass Family); Paniceae (Tribe) Wire Road Conservation Area, Stone County, Missouri Notes: Plant perennial, erect, to 70+ cm, some clumping; Culm terete, hairy or not, nodes with thick retrorse hairs, knotty rhizomes usually; Roots fibrous; Leaf blades up to 3.3+ cm, 3 to 6x longer than wide; Leaf Sheaths hairy, particularly on margins; Ligules of hair; Inflorescence a panicle up to 12-15+ cm, branches mostly spreading; spikelets 3+ to 5+ mm long, Glumes present, lower glume shorter than upper, upper glume almost as long as spikelet; 2 florets, lower floret usually staminate (might be sterile), upper floret perfect (see photos); many wooded habitats; late spring to early fall [V Max Brown, 2014] Leaf Blades up to 3.5 + cm Ligule of hairs, collar may be densely hairy Knotty rhizomes Nodes long retrorsely bearded Bosc's Panicgrass – p2 Dichanthelium boscii (Poir.) [V Max Brown, 2014] Spikelet with lower staminate floret and upper fertile floret, spikelet length in this case 4.5 mm (can vary from 3+ to 5+ mm) Upper Glume Lower Lemma Upper Glume, slightly shorter than spikelet Lower Glume Tiny tuft of hair often Lower staminate floret Upper fertile floret with removed from transparent spikelet palea Starved Panicgrass – p1 USDA Dichanthelium depauperatum (Muhl.) Gould Poaceae (Grass Family); Paniceae (Tribe) Near Bolivar, Polk County, Missouri Notes: Plant perennial, erect, to 45+ cm, cespitose; Culm terete, nodes bearded, internodes hairy or not; Roots fibrous; Leaf blades up to 5+ mm wide; Leaf Sheaths hairy as well as the back of the leaf blade; Ligules of hair; Inflorescence a panicle up to 6 to 8+ cm, branches strongly ascending; spikelets to 4.3+ mm; Glumes present, lower glume much shorter than upper, upper glume; 2 florets, lower floret usually sterile, upper floret perfect (see photos on p2); many habitats; summer to fall [V Max Brown, 2015] Starved Panicgrass – p2 Inflorescence an open Dichanthelium depauperatum (Muhl.) Gould panicle [V Max Brown, 2014] Spikelets terminal on branches, spikelet here is 3.5 mm (varies from 3.2 to 4+ mm), glabrous to slightly hairy Lower lemma upper glume Lower glume, somewhat pointed (triangular) at tip Fertile Upper floret, very hard, with small pointed tip; lower sterile floret inconspicuous Broadleaf Rosette Grass – p1 USDA Dichanthelium latifolium (L.) Gould & C.A. Clark Poaceae (Grass Family); Paniceae (Tribe) Wire Road Conservation Area, Stone County, Missouri Notes: Plant perennial, erect, to 120+ cm, some clumping; Culm terete, glabrous or hairy, rhizomes present; Roots fibrous; Leaf blades up to 4.0+ cm, 3 to 7x longer than wide, with many veins, base cordate and clasping; Leaf Sheaths hairy or not, collars hairy; Ligules very short, membranous and ciliate; basal leaves in rosette shorter than cauline leaves; Inflorescence a panicle up to 15+ cm long, branches mostly ascending to spreading; spikelets 3 to 4 mm long, some hairs; Glumes present, lower glume shorter than upper, upper glume almost as long as spikelet; 2 florets, lower floret usually staminate (might be sterile), upper floret perfect; many wooded habitats; late spring to early fall [V Max Brown, 2014] Broadleaf Rosette Grass – p2 Dichanthelium latifolium (L.) Gould & C.A.