마디풀속 Polygonum LINN.

1. 열매는 화피의 길이보다 짧다. 잎집에 가는 맥이 있고 끝에 털이 있다 ··························································· 247. 마디풀

1. 수과는 화피보다 길다.

2. 잎집은 짧고 맥이 적다 ··········································································································· 248. 큰옥매듭풀

2. 잎집은 길이 5-10rnrn로서 맥이 많다 ··························································································249. 이삭마디풀