KEY TO CLASSES OF VASCULAR PLANTS IN NEW SOUTH WALES | |
| 1 Plants not reproducing by seeds. | |
| 2 Stems prominently jointed: leaves whorled, forming a sheath at stem nodes. | CLASS 3 SPHENOPSIDA |
| 2* Stems not jointed; leaves absent or if present, not whorled and forming a sheath at the nodes. | |
| 3 Sporangia borne on stems, in the axils of leaves or leaf-like organs, or embedded in the expanded bases of such organs. | |
| 4 Sporangia fused to form synangia. | CLASS 1 PSILOPSIDA |
| 4* Sporangia not fused into synangia. | CLASS 2 LYCOPSIDA |
| 3* Sporangia borne otherwise (on leaves or in nut-like sporocarps). | CLASS 4 FILICOPSIDA |
| 1* Plants reproducing by seeds. | |
| 5 Ovules not enclosed in a carpel; ovules arranged in cones or solitary on a short fleshy axis (non-flowering seed plants). | |
| 6 Leaves pinnate. | CLASS 5 CYCADOPSIDA |
| 6* Leaves simple. | CLASS 6 CONIFEROPSIDA |
| 5* Ovules enclosed in a carpel; carpels arranged in flowers (flowering plants). | CLASS 7 MAGNOLIOPSIDA |
