겨이삭속 Agrostis LINN.

1. 소수에 까락이 있다.

2. 포영은 길이 2-3mm 이고 끼락은 외영의 중간이하에서 돋는다 ···························································· 193. 검정겨이삭

2. 포영은 길이 2mm 이하이다.

3. 까락은 외영에서 돋는다 ········································································································ 194. 검은겨이삭

3. 소수에 까락이 없다.

4. 내영은 외영길이의 1/3-1/2 이다.

5. 꽃차례는 위를 향한 가지 때문에 지름이 좁아진다········································································· 195. 흰겨이삭

5. 원추화서는 옆으로 퍼진다  ································································································ 196. 버들겨이삭

4. 내영은 매우짧다.

6. 내영은 외영길이의 1/3 정도이다.

7. 지하경이 있다 ··················································································································· 아기겨이삭

7. 지하경이 없다  ················································································································· 197. 겨이삭

6. 내영은 외영 길이의 1/3보다 짧다.

8. 잎혀는 길이 1.5~3mm이고 소수는 길이 1.5~5mm이다   ··························································198. 산겨이삭

8. 내앙은 길이 2mm 이상이다   ··························································································199. 긴겨이삭