The following dichotomous key can be used as a guide to identifying a particular blown-grass species. The key works by selecting one of the two choices given for each pair of descriptions, which lead to either another pair or the identification of your species.
1. | Leaves flat when fresh | 2 |
1. | Leaves inrolled or closely folded | 4 |
2. | Outer glumes of spikelets with a long awn-like bristle, flower-heads somewhat narrow and stiff with lower branches strongly deflexed (pointing backwards) | Lachnagrostis deflexa (Deflexed Blown-grass)# |
2. | Outer glumes finely pointed but without a bristle | 3 |
3. | Leaves less than 3 mm wide, flower-heads drooping or weeping | Lachnagrostis filiformis (Common Blown-grass) |
3. | Leaves greater than 3 mm wide, flower-heads more or less stiff and erect | Lachnagrostis billardierei (Coast Blown-grass) |
4. | Florets awnless or with non-bent or gently bent awns to 5 mm long or less | 5 |
4. | Florets with sharply bent awns, usually at least 5 mm long | 7 |
5. | Florets more or less awnless, floret hairy | Lachnagrostis leviseta (Awnless Blown-grass) |
5. | Florets with awns at least 1.5 mm long, floret hairless or sometimes with a few short hairs on the mid-back | 6 |
6. | Straight or slightly curved awn to 3 mm, arising from near floret tip; | Lachnagrostis adamsonii (Adamson’s Blown-grass |
6. | Straight or gently bent awn 3-5 mm long, arising from near mid-back of floret | Lachnagrostis sp.## |
7. | Upper part of florets with a rough surface | Lachnagrostis robusta (Salt Blown-grass) |
7. | Upper part of florets smooth | 8 |
8. | Lower parts of florets covered in hairs | Lachnagrostis punicea ssp. punicea (Purple Blown-grass) |
8. | Lower parts of florets hairless |
Purple Blown-grass (L. punicea ssp. punicea) | Salt Blown-grass (L. robusta) | Adamson’s Blown-grass (L. adamsonii) |
Common Blown-grass (L. filiformis) | Awnless Blown-grass (L. leviseta) | Coast Blown-grass (L. billardierei) |