Help with any of these would be appreciated. 14. No ideas on this small tree. Probably deciduous. Foliage is a bit dogwood-like. 15. Clearly a type of Rhus or Toxicodendron, but which. The leaflets are quite thick and leathery. Autumn colour is sometimes brilliant. Have never seen it in flower. 16. A spring-flowering perennial with velvety leaves. 17. A slowly spreading, evergreen groundcover with red young growth. Have observed this plant for about 15 years and it have never seen it flower. The general impression is a bit like that of some king of ground-hugging Pieris. Thank you for having a look and for any ideas. Geoff Bryant
Your first one with the yellow ball like flower, reminds me of a southeastern US native plant named Cephalanthus occidentalis. There are a couple of other Cephalanthus species, including one from Zimbabwe and one from southeast Asia. The venation on the leaves doesn't look quite like the one that I know, but that may be enough to trigger an association for someone here. The flower to fruit stages are variable in color, but are often lemony yellow early on, which would be mid spring or perhaps April for me.