Part 7 - UNC Herbarium

POACEAE 837
17 Pedicels of the pedicelled (reduced or absent) spikelets terete or slightly flattened and grooved
on one side only....................................................................................................... Andropogon
17 Pedicels of the pedicelled (reduced or absent) spikelets strongly flattened and grooved on both
sides, the central portion thin or membranous ........................................................Bothriochloa
References: Tucker (1996)=Z.
Aegilops Linnaeus 1753 (Goat Grass)
1 Spikelets cylindric; glumes with 4 awns; rachis disarticulating at maturity..........................................................Ae. cylindrica
1 Spikelets nearly ovate; glumes with 1 awn; rachis not disarticulating at maturity.................................................. Ae. neglecta
* Aegilops cylindrica Host, Jointed Goat Grass. Mt, Pd (VA): disturbed areas; uncommon, introduced from s. Europe. [= C,
F, G, HC, K, Z]
* Aegilops neglecta Req. ex Bertoloni, Small Goat Grass. Cp (VA): disturbed areas; rare, introduced from s. Europe.
Reported from Arlington County, VA. [= Z; Ae. ovata Linnaeus – C, G, HC, apparently misapplied; Ae. geniculata Roth – K,
apparently misapplied]
* Aegilops triuncialis Linnaeus. {MD} [= K] {not keyed at this time; synonymy incomplete}
Agropyron Gaertner 1770
(see Elymus, Elytrigia, Pascopyrum)
Agrostis Linnaeus 1753 (Bentgrass)
(also see Lachnagrostis and Polypogon)
A genus of about 220 species, primarily temperate. References: Tucker (1996)=Z.
1 Palea 1/2-3/4 as long as the lemma, 0.6-1.2 mm long; plants introduced, often (though not always) in disturbed habitats;
plants flowering (collectively) June-October; [subgenus Agrostis].
2 Ligule mostly 0.5-2 mm long, truncate; panicle branches naked towards the base, diffuse when in fruit, the spikelets
well-separated ..................................................................................................................................................A. capillaris
2 Ligule mostly 2.5-6 mm long, acute, rounded, or truncate; panicle branches (some of them) with spikelets to near the
base, the spikelets usually agglomerated.
3 Leaves 3-8 mm wide; inflorescence triangular-ovoid, the branches widely spreading at maturity, usually reddish;
plant with rhizomes, without stolons.........................................................................................................A. gigantea
3 Leaves mostly 1-3 mm wide; inflorescence narrowly ovoid, the branches ascending at maturity, usually tan; plant
without rhizomes, with or without stolons.
4 Stolons well developed; leaves mostly < 5 cm long................................................A. stolonifera var. palustris
4 Stolons poorly developed or absent; leaves mostly > 7 cm long......................... A. stolonifera var. stolonifera
1 Palea < 2/5 as long as the lemma, 0-0.5 mm long; plants native, typically in more or less natural habitats; plants flowering
(collectively) March-November; [subgenus Vilfa].
5 Lemma usually awned (sometimes unawned), the awn inserted near the apex, 4-10 mm long, straight, very delicate and
flexuous; annual, flowering April-June.......................................................................................................... A. elliottiana
5 Lemma awned or not, the awn (when present) inserted either near the middle of the lemma or near the apex, 0-6 mm
long, straight or bent, neither delicate nor flexuous; perennial, flowering (collectively) March-November.
6 Lemma with a 3-6 mm long, geniculate awn inserted near the middle; [of high elevation rock outcrops] .................
.................................................................................................................................................................A. mertensii
6 Lemma awnless or with a 0-3 mm long, straight awn inserted near the tip; [of various habitats].
7 Spikelets 1.2-2 mm long; anthers 0.3-0.6 mm long; plants flowering March-July........................... A. hyemalis
7 Spikelets (1.8-) 2.2-3.5 (-3.7) mm long; anthers (collectively) 0.3-1.2 mm long; plants flowering June-
November.
8 Leaves mostly involute, 1-2 (-3) mm wide; panicle branches mostly forking well beyond the middle.......
.....................................................................................................................................................A. scabra
8 Leaves flat, 2-6 mm wide; panicle branches mostly forking at or below the middle.
9 Lemma 1.8-3 mm long, minutely but copiously scabrous (at 20× or more); anthers 0.7-1.2 mm
long; spikelets (2.3-) 2.7-3.5 (-3.7) mm long, usually clustered near the tips of the branchlets;
panicle branches scabrous; culms to 15 dm tall; [of wet savannas and other wet habitats of the
Coastal Plain] ................................................................................................................... A. altissima
9 Lemma 1.4-2 mm long, glabrous; anthers 0.3-0.6 mm long; spikelets (1.8-) 2.2-2.7 (-3.2) mm long,
usually not clustered near the tips of the branchlets; panicle branches glabrous to scabrous; culms to
10 dm tall; [of various habitats, nearly throughout our area]..........................................A. perennans