산국수나무속 Physocarpus MAXIM.

1. 열매에 털이 없다. 잎은 둥근 난형이며 보통 5개로 갈라진다 ································································· 718+. 양국수나무

1. 열매에 털이 있다.

2. 잎은 얕게 또는 다소 깊게 3~5 개로 갈라지고 열매에 털이 많다.

    3. 잎은 3~5 개로 갈라지고 열편 끝이 뾰족하다     ···············································································716. 산국수나무

    3. 잎은 얕게 3 개로 갈라지고 열편 끝이 둔하다   ·············································································718. 중산국수나무

  2. 잎은 거의 갈라지지 않고 결각상이며 열매는 봉선을 따라 털이 있다    ······················································717. 섬국수나무