1 |
Annual or sometimes perennial, keels of palea with flexuous, curved or crispate hairs along their whole length (or almost so) |
|
(2) |
+ |
Perennial or rarely annual; keels of palea scabrid or prickly, if hairy then only in the lower half |
|
(5) |
|
|
|
|
2 (1) |
Lower panicle-branches erecto-patent after anthesis; spikelets with rather distant florets; anthers 0.2-0.5 mm long, scarcely longer than wide |
|
Poa infirma |
+ |
Lower panicle-branches spreading or deflexed after anthesis; spikelets with crowded florets; anthers 0.6-2mm long, at least twice as long as wide |
|
(3) |
|
|
|
|
3 (2) |
Spikelets not crowded towards the ends of the panicle-branches; anthers 0.6-0.8 (-1) mm long, 2-3 times as long as wide |
|
(4) |
+ |
Spikelets crowded towards the ends of the panicle-branches; anthers usually 1.3-2 mm long, 5-8 times as long as wide |
|
Poa supina |
|
|
|
|
4 (3) |
Lemma with copious wool at the base |
|
Poa nepalensis |
+ |
Lemma without any wool at the base |
|
Poa annua |
|
|
|
|
5 (1) |
Stem with a bulbous swelling at the base formed from the hardened remains of old leaf-sheaths |
|
(6) |
+ |
Stem not bulbous at the base, but sometimes thickened with the scarious or fibrous (not hardened) remains of old leaf-sheaths |
|
(8) |
|
|
|
|
6 (5) |
Lemma entirely hairless though often scabrid |
|
Poa bactriana |
+ |
Lemma ciliate, or at least thinly hairy, on the keel and marginal nerves |
|
(7) |
|
|
|
|
7 (6) |
Lemma with wool at the base, this usually copious; lemmas 2.5-3.5mm long; anthers 1-1.5mm long (or spikelets usually proliferating and these characters not visible) |
|
Poa bulbosa |
+ |
Lemma without wool at the base (or sometimes just 1 or 2 strands); lemmas 3.5-5mm long; anthers 1.5-2.5mm long (spikelets rarely proliferating in our area) |
|
Poa sinaica |
|
|
|
|
8 (5) |
Robust perennial up to 120 cm high; lemma entirely glabrous; panicle narrow; species only in cultivation |
|
Poa ampla |
+ |
Plant not as above; if lemma glabrous then plant not over 40cm high and panicle ovate or pyramidal; native wild specie |
|
(9) |
|
|
|
|
9 (8) |
Lemma hairy on the surface between the nerves (this may be extremely sparse) or sometimes only shortly asperulous |
|
(10) |
+ |
Lemma glabrous on the surface between the nerves although the keel and marginal nerves are usually ciliate below |
|
(17) |
|
|
|
|
10 (9) |
Palea-keels ciliate below, scabrid above |
|
(11) |
+ |
Palea-keels scabrid throughout their length. |
|
(14) |
|
|
|
|
11 (10) |
Stoloniferous plant with culms often ascending from a procumbent base which sometimes roots from the lower nodes; panicle loose, 12-25cm long |
|
Poa stapfiana |
+ |
Tufted plants without stolons; culms not rooting from the lower nodes; panicle lax or dense |
|
(12) |
|
|
|
|
12 (11) |
Spikelets, when young, broadly ovate; leaf-blades 4-12cm long, 2-5mm wide; panicle compact or spreading, 3-7cm long; culms clothed at the base with the fibrous remains of old leaf-sheaths |
|
Poa alpina |
+ |
Spikelets, when young, elliptic or lanceolate; leaf-blades up to 6cm long and 1.5mm wide; panicle contracted, 0.5-5cm long; culms clothed at the base with the scarious remains of old leaf-sheaths |
|
(13) |
|
|
|
|
13 (12) |
Dwarf plants up to 10(-15)cm high; wool present at the base of the lower lemmas; leaf blades up to 2cm long |
|
Poa koelzii |
+ |
Taller plants up to 30 cm high; wool absent or extremely sparse; leaf-blades 2-6cm long |
|
Poa lahulensis |
|
|
|
|
14 (10) |
Tufted plants with rhizomes; panicle contracted, spike-like; lemma asperulous all over the back; palea-keels with prickles below and teeth above |
|
Poa tibetica |
+ |
Tufted plants without rhizomes, though sometimes with stolons; panicle lax or effuse, not spike-like; lemmas shortly hairy or with a felty pubescence between the nerves below; palea-keels evenly scabrid or prickly |
|
(15) |
|
|
|
|
15 (14) |
Lower glume subulate-acuminate in side-view, 1-nerved; lemmas obtuse; plant stoloni¬ferous |
|
Poa polycolea |
+ |
Lower glume elliptic or oblong, 1-3-nerved; lemmas acute or obtuse; plant tufted, the culms sometimes decumbent at the base and rooting from the lower nodes, but the plant not other-wise spreading by stolons |
|
(16) |
|
|
|
|
16 (15) |
Slender grass; lemmas very blunt, scabrid on the back and with either a few short hairs or a felty pubescence between the nerves below; spikelets ovate-elliptic, up to 5.5mm long |
|
Poa pagophila |
+ |
Robust grass; lemmas acute, gland-pitted on the back and with short, rather coarse hairs below; spikelets 7-8mm long, the florets eventually widely diverging |
|
Poa falconeri |
|
|
|
|
17 (9) |
Palea-keels ciliate below, scabrid above |
|
(18) |
+ |
Palea-keels scabrid ± throughout their length |
|
(19) |
|
|
|
|
18 (17) |
Base of the lemma without any wool |
|
Poa sikkimensis |
+ |
Base of the lemma with copious wool |
|
Poa stewartiana |
|
|
|
|
19 (17) |
Plants rhizomatous |
|
(20) |
+ |
Plants not rhizomatous |
|
(23) |
|
|
|
|
20 (19) |
Lemmas very broad, not strongly keeled on the back, rounded and broadly hyaline at the tip |
|
Poa calliopsis |
+ |
Lemmas strongly keeled on the back, acute or narrowly obtuse at the tip, narrowly hyaline at most |
|
(21) |
|
|
|
|
21 (20) |
Uppermost node in the median third of the culm or above; plant loosely or densely tufted from a slender rhizome |
|
(22) |
+ |
Uppermost node in the basal third of the culm; plant densely tufted from a short thick rhizome |
|
Poa versicolor subsp. araratica |
|
|
|
|
22 (21) |
Panicle narrow, few-spiculate, the branches 2-3 at the lower nodes; ligule 1.5-3mm long (if ligule not more than 1 mm see 21. P. nemoralis) |
|
Poa sterilis |
+ |
Panicle lanceolate to ovate, with many spikelets, often rather dense, with 3-5 branches at the lower nodes; ligule 1-3mm long (if ligule 3.5-10 mm long see 20. P. trivialis) |
|
Poa pratensis |
|
|
|
|
23 (19) |
Anthers 0.6-0.75 mm long |
|
Poa setulosa |
+ |
Anthers 1.3-2.5mm long |
|
(24) |
|
|
|
|
24 (23) |
Ligule pointed, 3.5-10 mm long |
|
Poa trivialis |
+ |
Ligule pointed or blunt, not more than 3mm long |
|
(25) |
|
|
|
|
25 (24) |
Ligule very short, scarcely exceeding 1mm in length |
|
(26) |
+ |
Ligule longer, 1-3 mm long |
|
(27) |
|
|
|
|
26 (25) |
Anthers 1.3-2mm long; lower glume 3-nerved; panicle-branches scaberulous, 2-5 at the lower nodes |
|
Poa nemoralis |
+ |
Anthers 1.8-2.5 mm long; lower glume 1-nerved; panicle-branches smooth, paired at the lower nodes |
|
Poa aitchisonii |
|
|
|
|
27 (25) |
Tall plant, usually 40-120cm high; spikelets ovate or oblong, not becoming wedge-shaped; panicle ample, 10-20(-30)cm long, with branches in distant clusters of 3-6 at a node |
|
Poa palustris |
+ |
Smaller plants, but sometimes reaching 40cm in height; spikelets often becoming wedge-shaped; panicle not ample, either short (2-10cm long) and dense or longer (7-15cm long) but with relatively few spikelets |
|
(28) |
|
|
|
|
28 (27) |
Plant stoloniferous, the culms erect or geniculately ascending from a creeping base; panicle very loose and spreading |
|
Poa polycolea |
+ |
Plant tufted, not stoloniferous, the culms usually erect; panicle narrow, lax or dense |
|
(29) |
|
|
|
|
29 (28) |
Uppermost node in the median third of the culm |
|
Poa sterilis |
+ |
Uppermost node in the basal third of the culm |
|
(30) |
|
|
|
|
30 (29) |
Lowest lemma (2-)2.3-3(-3.2)mm long; spikelets usually 3-4mm long |
|
Poa attenuata |
+ |
Lowest lemma (2.8-)3-4.5mm long; spikelets 3-6.5mm long |
|
(31) |
|
|
|
|
31 (30) |
Green or glaucous plant, usually 25-50cm high; uppermost node about a third the way up the culm |
|
Poa versicolor subsp. araratica |
+ |
Very glaucous plant 10-25cm high (rarely higher); uppermost node in the lowest sixth of the culm |
|
Poa glauca subsp. litwinowiana |