While it is fairly large in size, this woodland bluegrass has a delicate appearance with airy panicles of spikelets. In general, the Poa spp. (Bluegrasses) are difficult to identify. Most guides distinguish different species of bluegrass by the appearance of their lemmas – in particular, the presence or absence of fine hairs at the base of the lemma and along its veins. This requires a hand lens with about 10x magnification, and even then it can be difficult to discern these hairs. In this regard, the lemmas of Woodland Bluegrass are hairier than most other species in this genus; each of its lemmas has fine hairs at the base and along all of the veins (at least along the lower half of the lemma). Some other distinguishing characteristics of this species include the following: 1) the blades of its leaves are wider (up to 6 mm.) than those of many other bluegrasses, and 2) the widely spreading branchlets of its panicles have a tendency to hang downward with age (particularly the lower ones). Other bluegrasses have branchlets that are ascending to spreading and they don't hang downward at maturity.

This native grass is a loosely tufted perennial about 2-3' tall, sending up several unbranched culms. Each culm has 4-5 alternate leaves along its length; it is terete or slightly flattened, light green, and glabrous. The leaf blades are up to 5" long and ¼" (6 mm.) across; they are widely spreading or slightly drooping, dull green, and hairless. The tips of the blades are keel-shaped, while their margins are rough. The leaf sheaths are dull green, hairless to minutely pubescent, and open. At the junction of each blade and sheath, there is a white membranous ligule about 1-2 mm. long; it is partially exerted above the blade. Each culm terminates in a panicle of spikelets about 4-8" long and half as much across at the base; it is pyramidal or conical in overall shape and airy in appearance. Along the central axis (rachis) of each panicle, there are whorls of 3-5 branchlets that often subdivide into smaller branchlets. These branchlets are slender, hairless, and widely spreading; as the inflorescence ages, the lower branchlets often hang downward. At the tip of each branchlet, there is a spikelet about 4 mm. long and 2 mm. across that is somewhat flattened and light green; it consists of a pair of glumes and 2-4 lemmas. The light green glumes are lanceolate with membranous margins; the smaller glume is 1.5–2.0 mm. long, while the larger glume is 2.5–3.0 mm. long. The light green to green lemmas are lanceolate-oblong, and keeled; each lemma is about 3.0 mm. long with 5 fine nerves (along the keel, both margins, and between the keel and margins). These nerves are finely pubescent (at least along the lower half of each lemma), while at the base of each lemma, there is web of fine hairs. The blooming period occurs from late spring to early summer. Shortly afterwards, this grass becomes yellow and fades away by the end of summer. Each fertile lemma produces a single grain. Disarticulation is above the glumes. The root system is fibrous; it doesn't produce rhizomes or stolons. This grass occasionally forms colonies by reseeding itself.

Poa sylvestris A. Gray:
Canada (North America)
United States (North America)

Canada

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

United States

Origin: Unknown/Undetermined

Regularity: Regularly occurring

Currently: Unknown/Undetermined

Confidence: Confident

Global Range: This grass may be found from New York west to Wisconsin and Iowa, and south to Florida and Texas.

Woodland Bluegrass is occasional throughout Illinois (see Distribution Map). Habitats include rich deciduous woodlands, wooded ravines, and rocky wooded slopes. This species is restricted to woodlands where the original ground flora is still intact. It is the most common woodland bluegrass in Illinois.

Perennials, Terrestrial, not aquatic, Stems nodes swollen or brittle, Stems erect or ascending, Stems geniculate, decumbent, or lax, sometimes rooting at nodes, Stems caespitose, tufted, or clustered, Stems terete, round in cross section, or polygonal, Stem internodes hollow, Stems with inflorescence less than 1 m tall, Stems, culms, or scapes exceeding basal leaves, Leaves mostly basal, below middle of stem, Leaves conspicuously 2-ranked, distichous, Leaves sheathing at base, Leaf sheath mostly open, or loose, Leaf sheath smooth, glabrous, Leaf sheath or blade keeled, Leaf sheath and blade differentiated, Leaf blades linear, Leaf blades 2-10 mm wide, Leaf blades mostly flat, Leaf blades mostly glabrous, Ligule present, Ligule an unfringed eciliate membrane, Inflorescence terminal, Inflorescence an open panicle, openly paniculate, branches spreading, Inflorescence solitary, with 1 spike, fascicle, glomerule, head, or cluster per stem or culm, Inflorescence lax, widely spreading, branches drooping, pendulous, Inflorescence with 2-10 branches, Inflorescence branches more than 10 to numerous, Lower panicle branches whorled, Flowers bisexual, Spikelets pedicellate, Spikelets laterally compressed, Spikelet less than 3 mm wide, Spikelets with 2 florets, Spikelets with 3-7 florets, Spikelets solitary at rachis nodes, Spikelets all alike and fertille, Spikelets bisexual, Spikelets disarticulating above the glumes, glumes persistent, Spikelets disarticulating beneath or between the florets, Rachilla or pedicel glabrous, Glumes present, empty bracts, Glumes 2 clearly present, Glumes equal or subequal, Glumes distinctly unequal, Glumes shorter than adjacent lemma, Glumes keeled or winged, Glumes 3 nerved, Lemmas thin, chartaceous, hyaline, cartilaginous, or membranous, Lemma similar in texture to glumes, Lemma 5-7 nerved, Lemma glabrous, Lemma body or surface hairy, Lemma apex truncate, rounded, or obtuse, Lemma awnless, Lemma margins thin, lying flat, Lemma straight, Callus or base of lemma evidently h airy, Callus hairs shorter than lemma, Lemma with long cobwebby white hairs, Palea present, well developed, Palea about equal to lemma, Palea 2 nerved or 2 keeled, Stamens 3, Styles 2-fid, deeply 2-branched, Stigmas 2, Fruit - caryopsis, Caryopsis ellipsoid, longitudinally grooved, hilum long-linear.

Woodland Bluegrass is occasional throughout Illinois (see Distribution Map). Habitats include rich deciduous woodlands, wooded ravines, and rocky wooded slopes. This species is restricted to woodlands where the original ground flora is still intact. It is the most common woodland bluegrass in Illinois.

While floral-faunal relationships for Poa spp. (Bluegrasses) that grow in meadows are fairly well known, there is less information available for woodland bluegrasses. The foliage and seeds of the latter are eaten by the Wild Turkey and Ruffed Grouse. White-Tailed Deer tend to avoid woodland bluegrasses, preferring to browse on broad-leaved forbs. Photographic Location: A mesic area of Busey Woods in Urbana, Illinois.

Note: For many non-migratory species, occurrences are roughly equivalent to populations.

Estimated Number of Occurrences: > 300

Collection Sites: world map showing specimen collection locations for Poa sylvestris

Barcode of Life Data Systems (BOLD) Stats
                                                             

Specimen Records:	3
Specimens with Sequences:	5
Specimens with Barcodes:	3
Public Records:	0
Species:	1
Species With Barcodes:	1

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 0
Species: 3
Species With Barcodes: 1

Canada

Rounded National Status Rank: N1 - Critically Imperiled

United States

Rounded National Status Rank: NNR - Unranked

Rounded Global Status Rank: G5 - Secure

This grass prefers dappled sunlight to light shade, moist to mesic conditions, and a rich loamy soil. Most vegetative growth occurs during the spring.