|  | Multitribe: Answers to key questions
    leading to this tribe. 
     
      |  | Mature inflorescence, if breaking into units, then the units not as
        below; NOT [Mature inflorescence breaking into spikelet units consisting
        of a sessile fertile spikelet, a hairy pedicel with or without a sterile
        spikelet at tip, and a hairy rachis joint, all arising at the same point
        (a node) in specialized panicle branches called rames] |  |  | Spikelets not as below; sterile florets if present, either located
        distal to the fertile floret(s) on the rachilla or paired and attached
        at the base of a single fertile floret, not paired with the upper glume
        as below; lemma and palea variously textured, enclosing the flower or
        not; disarticulation usually above the glumes; NOT [Spikelets usually
        dorsally compressed, appearing 1-flowered but containing 1 fertile
        floret and 1 sterile floret, the latter attached to the base of fertile
        floret opposite the upper glume, resembling the upper glume, and
        together with the upper glume enveloping the fertile floret; lower
        glumes minute (sometimes absent) to 3/4 as long as upper glumes and
        typically wrapping most of the way around the pedicel at base; fertile
        floret seed-like with chartaceous-indurate lemma and palea enclosing
        flower and fruit; disarticulation below the glumes with rare exceptions] |  |  | Spikelets 1 to many-flowered, subtended by a pair of glumes (only 1 on
        lateral spikelets in Lolium); palea margins enclosed or not; plants of
        dry or wet habitats; NOT [Spikelets 1-flowered, lacking glumes; margins
        of the palea tightly enclosed by the lemma margins on female or perfect
        florets; plants of wetlands, often emergent aquatic] |  |  | Inflorescence not as below; if a terminal spike, then the lateral
        spikelets attached edgewise to the rachis with inner (upper) glume
        wanting (as in Lolium); NOT [Inflorescence a terminal spike with sessile
        or subsessile spikelets attached broadside at nodes on opposite sides of
        the rachis] |  |  | Lemmas and lemma awns not as below; if lemma indurate and enveloping
        the floret, then glumes distinctly dorsally compressed and calluses
        glabrous (as in Milium); NOT [Lemmas stiff to indurate, firmer than the
        glumes, surrounding the palea and often overlapping along the margins,
        closed at the tip as well as at the base, often pubescent; lemma awns
        (caducous or wanting in some species) terete and encircled at the base
        by the closed tip of the lemma; calluses usually pubescent, rarely
        glabrous] 
 
 |  | 
  |  | Group1: Answers to key questions
    leading to this group. 
     
      |  | If plants mat-forming, then inflorescences not as below; NOT
        [Mat-forming annuals or perennials either with clusters of spikelets
        hidden by sharp-pointed leaves at branch tips, or with pistillate
        inflorescences consisting of burs partially hidden within expanded leaf
        sheaths with only the staminate inflorescences exceeding the upper
        leaves] |  |  | Inflorescence consisting of spike-like panicle branches with sessile-
        subsessile, closely imbricate, regularly-spaced, parallel spikelets all
        directed toward 1 side of the branch like the teeth of a comb (loosely
        so in Bouteloua curtipendula); fertile florets 1 per spikelet; NOT
        [Inflorescence not as above, the spikelets usually on pedicels in
        panicles that range from spike-like to open; if spikelets sessile, then
        they either have more than 1 fertile floret per spikelet or are not
        arranged like the teeth of a comb] 
 
 |  |  | Beckmannia: Answers to key questions
    leading to this genus. 
     
      |  | Glumes subequal, D-shaped in side view, about 3 mm long; ligules 5-11
        mm long, membranous, entire or lacerate; NOT [Glumes unequal, the lower
        glume distinctly narrower and shorter than the upper glume, upper
        (exterior and longer) glume (2.5) 3.5-25 mm long; ligules <= 3 mm
        long, a fringe of hairs with or without a membranous base] |  |  |