명아주속 Chenopodium LINN.

1. 잎은 뒷면에 선모가 없다

2. 잎은 피침형이며 톱니가 없고 꽃차례의 잔가지는 가시같이 생겼다  ························································252. 바늘명아주

2. 잎은 보다 넓고 가시가 없다.

3. 식물체는 곧추 자란다.

4. 잎에 톱니가 없다.

5. 잎은 얇고 때로 불규칙한 톱니가 있다.

6. 잎의 밑부분이 갈라져서 창검형으로 되는 것이 있다. 종자는 검고 윤채가 없다   ······························· 254. 청명아주

6. 불규칙한 톱니가 있기도 하고 종자에는 잔주름이 있다  ····························································· 255. 참명아주

5. 잎은 두껍고 좁은 피침형이며 톱니가 전혀 없고 어릴 때 뒷면에 흰가루 같은 돌기가 밀생한다   ············· 256. 버들명아주

4. 잎에 톱니가 있다.

7. 잎은 분백색이다.

8. 잎에 불규칙한 톱니가 있고 종자에 윤채가 있다  ········································································258. 명아주

8. 잎은 얕게 3개로 갈라지고 종자에 윤채가 없다  ·······································································259. 좀명아주

7. 잎은 녹색이며 잎은 넓은 난형이고 톱니가 있다  ······································································260. 앓은명아주

3. 식물체는 비스듬히 눕는다. 잎의 표면은 녹색이고 뒷면은 분백색이다  ····················································257. 취명아주

1. 식물체, 특히 잎뒷면에 선점이 있다 ·································································································· 253. 양명아주