This feature covers arrangement of leaves on elongate stems. If a plant has a compact stem, this feature usually does not apply. However, If you can observe phyllotaxis on a compact stem, this feature may apply.
For both erect and horizontal (creeping or floating) stems, a stem with
alternatealternate:
(adj) (of leaves) bearing one leaf per node; placed singly on the stem at different heights
phyllotaxis has one leaf at each node, oppositeopposite:
(adj) (of leaves) two leaves per node; in pairs on opposite sides of an axis
has two, and
whorledwhorled:
(n) bearing whorls; a type of leaf arrangement (phyllotaxis) in which leaves are in whorls
has more than two.