Habit

The habit of a plant refers to its visual general appearance and form and can be considered as a collection of different features which aid identification.

Habit can cover features such as:
Stem (e.g. upright, spreading, stolon, rhizome).
Leaf shape (e.g. oval, linear).
Leaf arrangement on stem (e.g. alternate, opposite).
Leaf type (e.g. simple, compound).
Life cycle (e.g. annual, perennial).
Presence and types of fruit (e.g. pome, drupe).
Flower types and arrangements (e.g. single, inflorescence).
Its seasonal appearance (e.g. deciduous, evergreen).
Seasonal growth (e.g. woody, herbaceous).

Life form looks at the size of a plant, for example is it, in general, low growing, a shrub or a tree?

Life forms were formally classified by the Danish botanist Raunkier, who grouped plants according to the location of their resting buds during winter.

There are 5 main classifications:
1. Therophytes: annuals and ephemerals which over-winter as seed (the resting bud is the embryo);
2. Cryptophytes, of which one sub-division is Geophytes, which are perennials that over-wintered below ground, e.g. bulbs, rhizomes;
3. Hemicryptophytes: perennials at soil level, e.g. daisy plant;
4. Chamaephytes: perennials, such as low shrubs, buds up to 25cm from soil level;
5. Phanerophytes: perennial, shrubs and trees, buds at greater than 25 cm from soil level.

Plant growth habit might also be categorised as follows:
1. Forb / herb: plants that lack secondary thickening.
2. Graminoid: grass or grass-like.
3. Lichenous: lichens.
4. Liana: tropical climbing plants.
5. Non-vascular: mosses, liverworts.
6. Shrub: usually up to 5m in height.
7. Sub-shrub: low shrub usually less than 0.5m in height.
8. Tree: usually greater than 5m in height.
9. Unknown: especially if you are unsure of likely height.
10. Vine: climbing plant.