Vegetative key to the families

GRASSES. Herbs. Leaf bases modified to form an open sheath which encloses the stem; leaf blade with parallel venation and abruptly distinct from the sheath; LIGULE usually present at the top of the sheath (Fig 24) Poaceae
PALMS. Leaves large, pinnately or palmately divided, the segments with parallel venation; leaf bases enclosing or clasping the stem. Young inflorescences enclosed by a large deciduous spathe Arecaceae
STEMS SQUARE (or quadrangular), smooth or hairy but not scabrous; leaves opposite or rarely whorled, fragrant but usually without oil dots; fruit separating into 4 articles Lamiaceae
HAIRS WITH SWOLLEN BASES present on leaves and stems. Herbs; whole plant scabrous and raspy to the touch; leaves alternate. Inflorescence cymose Boraginaceae
OCHREA (sheath) Present around the stem and petiole, formed from fused stipules (Fig. 25). Leaves alternate. Herbs Polygonaceae
Herbs with SWOLLEN NODES and opposite or rarely whorled leaves; leaves always simple with entire margins; the leaf bases often connate. Stipules mostly absent, sometimes membranous and connate Caryophyllaceae
WOODY PLANT(usually shrubs) with leaves with PARALLEL VENATION (Fig. 26). Leaves alternate or spirally arranged, often crowded, rigid, ericoid, often sharp-pointed; the margins usually entire but sometimes denticulate; stipules absent Ericaceae
PHYLLODES present with a raised or depressed extra-floral nectary on the adaxial edge, hanging or standing with the nectary uppermost. (A few species of Acacia with exceptional additional structures are included in the key below) (Mimosoideae Fabaceae
INSECTIVEROUS PLANTS with either sticky glands on the leaves (Fig.28), or with bladders 1–2 mm long on submerged or subterranean leaves (Fig. 28). Very delicate herbs
FREE FLOATING WATER PLANTS; roots, when present, not rooted in the mud. (Note: there are 2 genera of ferns which are free floating, see Azolla and Salvinia)
Submerged plants rooted in mud. Leaves submerged or floating on the surface or sometimes the leaf blades held erect above the water surface. Freshwater or marine (Amphibious plants are not included in this group)
MANGROVES. Woody plants growing in saline mud near the coast
ROOTLESS EPIPHYTIC PARASITES.
TENDRILS present on stem or leaves; plants climbing or decumbent
LEAVES REDUCED TO SCALES ON THE AERIAL STEMS
EPIPHYTES on trees or rocks
LATEX (milky white or yellow) present in stem and leaves
Either: leaves whorled; or leaves opposite and interpetiolar stipules present (Fig. 29). Herbs and woody plants
Remaining groups