Trochodendraceae

The Trochodendraceae is a small family of dicotyledonous flowering plants, consisting of two genera of evergreen trees: Trochodendron and Tetracentron. These trees are notable for lacking specialized water-conducting vessel cells in their wood, instead using tracheids, a type of cell more commonly found in gymnosperms.1

Trochodendron aralioides, known as the wheel tree, is found in East Asia and has flowers that lack sepals and petals. These flowers can be male-only or bisexual, featuring a ring of stamens and partially fused carpels. Tetracentron sinense, native to China, Nepal, and Myanmar, has bisexual flowers arranged in catkins and possesses four tepals, four stamens, and four carpels. Both species are occasionally cultivated as ornamentals.1