MONOCOTS: SEDGES AND GRASSES

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Survey of Monocots: Commelinids

Order Poales - part 2: the wind pollinated families - see APGII phylogeny

Typhaceae (cattail family)

Perianth parts hair-like
Inflorescence aroid-like

Typha latifolia (common cattail)
Typha angustifolia (narrow-leaved cattail)

Sparganiaceae (bur-reed family)

Perianth parts scale-like
Inflorescences separate

Sparganium americanum (bur-reed)

Xyridaceae

4 genera and 200 species

Xyris (yellow-eyed grass)

Eriocaulaceae

Eriocaulon septangulare = E. aquaticum (pipewort)

Juncaceae (rush family)

Grass or sedge like
6 perianth parts
3-numerous ovules per fruit
CA3 CO3 A6 G3 (1 locule)

Juncus tenuis (rush)
Luzula multiflora (wood rush)

 

Grasses and sedges - convergent reduction to wind pollination

Linear leaves with blade and sheath
Small, naked flowers with scale or hair-like perianth
Stamens 6, 3, or 1
1 pistil (but from 2 or 3 carpels)
1 locule, 1 seed
Fruit a caryopsis (=grain) or achene

ecological specialization

Ultimate in floral reduction in Commelinids
Spikelet = ecological equivalent of "flower"

 

Cyperaceae (sedge family)

Flowers perfect or unisexual; flowers subtended by 1 bract

14 genera in Wisconsin

Cyperus lupulinus macilentus [= filiculmis] (nut grass, umbrella sedge)
Scirpus atrovirens (bulrush)
S. cyperinus (wool grass)
Carex buxbaumii, hystericina, plantaginea, pensylvanica (sedges)
Eriophorum (cotton or bog grass)
Fuirena (umbrella grass)
Eleocharis (spike rush)
Dulichium (3-way sedge)


Poaceae or Gramineae (grass family)

The most important plant family in the world
Taxonomic confusion within and among families
molecular evidence for familial relationships

Terms

ligule
intercalary meristem
spikelet, glume, palea, lemma, lodicules
caryopsis or grain

 

Recent classification

 

subf. Anomochlooideae

Anomochloa & Streptochaete - herbaceous bamboos of neotropics
sister to all other grasses

subf. Pharoideae

herbaceous and pantropical

 

BEP clade

subf. Bambusoideae (tribe Bambuseae)

Primitive floral structure
Advanced woody vegetative structure
Bambusa
Chusquea
Phyllostachys

subf. Ehrhartoideae

Oryza sativa (rice)
Zizania aquatica (Indian or wild rice)

subf. Pooideae

Poa (bluegrass)
Bromus (bromegrass)
Dactylis glomerata (orchard grass)
Agrostis gigantea (redtop)
Stipa spartea (needle grass, porcupine grass)
Ammophila breviligulata (marran grass, beach grass)
Calamagrostis canadensis (blue joint grass)
Phalaris arundinacea (reed canary grass)
Phalaris canariensis (canary grass)
Hierochloe odorata (sweet grass)
Avena fatula (wild oats)
Hordeum (barley)
Triticum and Aegilops (wheat and ancestors)
Secale (rye)
Agropyron repens (quack grass)
A. trachycaulum (wheat grass)
Elymus canadensis (wild rye)
Hystrix patula (bottlebrush)

 

PACCAD clade

subf. Arundinoideae - possibly not a natural subfamily

Phragmites (reed)
Cortaderia (horticultural plume grass)

subf. Aristidoideae - possibly not a natural subfamily

Aristida tuberculosa (3 awned grass)

subf. Chloridoideae - predominantly C4 arid/semiarid plants

Bouteloua curtipendula (side oats gramma)
Spartina pectinata (prairie cord grass)
S. alterniflora (seaside cord grass)
Eragrostis (lovegrass)
Muhlenbergia glomerata (wild marsh timothy)
Sporobolus (prairie dropseed)

subf. Panicoideae

- Spikelet with 2 florets
- the bottom reduced and sterile
- articulation below glumes
- spikelets compressed perpendicular to plane of arrangement of glumes and florets

Tribe Paniceae

Digitaria (crabgrass)
Panicum virgatum (switch grass)
P. miliaceum (millet)
Setaria viridis, glauca (foxtail)

Tribe Andropogoneae - spikelets paired

Andropogon gerardii (big bluestem, turkeyfoot)
Schizachyrium scoparium [=Andropogon scoparius] (little bluestem)
Sorghastrum nutans (Indian grass)
Sorghum vulgare (sorghum)
Saccharum (sugar cane)
Zea mays (maize)
Tripsacum (teosintes)

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