Quiz #3, 9 October 2009. Answers

1. Stipa richardsonii. What inflorescence trait distinguishes this species? Open panicle

2. Helictotrichon hookeri. Are the florets of this genus dimorphic? No

3. Holcus lanatus. Describe the diagnostic leaf sheath of this genus? Velvety hairy

4. Stipa viridula. Describe the diagnostic leaf sheath of this species? Hairy collar or margins

5. Oryzopsis hymenoides. What inflorescence trait distinguishes this species? Dichotomous branching

6. Arrhenatherum vs Helictotrichon. How do the spikelets mainly differ between these two genera? Dimorphic vs monomorphic

7. Anthoxanthum hirtum. Describe the diagnostic dimorphic florets of this species? Lower two florets are hairy (staminate) and the upper is glabrous (seed bearing)

8. Anthoxanthum odoratum. Describe the diagnostic glumes of this species? The first glume is very short

9. Avena fatua. What distinguishes this species as NOT being cultivated? Hairy callus and long bent awns

10. Piptochaetium fimbriatum. What distinguishes the tribe to which this species belongs? Papery glumes and hardened lemma that wraps around palea and flower

11. Ventenata dubia. What is the single most diagnostic trait of this genus? Ribbed glumes

12. Arrhenatherum elatius. What distinguishes the tribe to which this species belongs? Glumes that enclose floret cluster, awn from lemma back

13. Stipa nelsonii. Is this a species of the open plains or mountains? Mountains (its counterpart Stipa viridula is from the open plains)

14. Beckmannia syzigachne. What is this species (genus and species)? Beckmannia syzigachne

15. Avena sativa. What distinguishes this species as being cultivated? No callus and no or small straight awns

syllabus