VEGETATIVE MORPHOLOGY

The Life Span of an Individual PlantAnnual Lives for a single growing season.Biennial Lives for two seasons, growing vegetatively during the first and flowering in the second.Perennial Lives for three or more years and usually flowers and fruits repeatedly.

Plant HabitHerbSubshrub (Suffrutescent plant)ShrubTreeSucculentVineLianaEpiphyte

HerbHelianthus maximiliani Schrad.

SubshrubGutierrezia sarothrae

ShrubArtemisia tridentata

TreeSequoia sempervirens

SucculentCactaceae

VineConvolvulus arvensis L.

LianaParthenocissus inserta

EpiphytesOrchids, bromeliads,and others

RootsUsually cylindrical plant axes that lack external nodes and buds. Branch roots arise from the interior of other roots. Usually the portion of a plant that absorbs water and minerals. Most commonly, roots are underground structures, but some plants produce above-ground roots.

Types of RootsAdventitious From stem or leaf tissue rather than the interior of another root.Fibrous With all portions of the root system of more or less equal thickness, often well branched, and the primary root (taproot) absent or not obvious.Taproot The major root, usually enlarged and growing downward.

Other Types of RootsAerial Growing above ground or water.Fleshy Thick with water or carbohydrate storage tissue.Haustorial Specialized for penetrating other plants and absorbing water and nutrients from them (as in parasites).

Stem TypesAerial stem Prostrate to erect above-ground stems. These are the most commonly encountered types of stems.Rhizome Elongated, underground horizontal stem.Stolon Above ground, horizontal stems called runners.

More Stem TypesBulb An underground stem with many fleshy scale leaves filled with stored food.Corm A solid underground stem in which food is stored.Tuber A much enlarged, short, fleshy, underground stem.

More Stem TypesBulb An underground stem with many fleshy scale leaves filled with stored food.Corm A solid underground stem in which food is stored.Tuber A much enlarged, short, fleshy, underground stem.

Stem Features 1/4Node The position on a stem where a leaf was or is attached.Internode The part of a stem axis between two nodes.Axil The upper angle formed by a leaf and the twig to which the leaf is attached. Typically, an auxillary bud (lateral bud) forms in each leaf axil.

Stem Features 2/4Bud An external meristem (either naked or protected by bud scales) found on stems. A bud may give rise to a leafy stem, a flower or a combination of vegetative and reproductive structures.Axillary bud A bud borne in the axil of a leaf; a lateral bud.Terminal bud A bud borne at the end of a stem.

Stem Features 3/4Bud scales Scale leaves that cover and protect terminal and axillary buds.Bud scale scars The rough places or scars left on a stem when bud scales fall off.Stipule scars A pair of rough places or scars (or sometimes a single ring-like scar) left when stipules fall from a twig.

Stem Features 4/4Leaf scar The rough place or scar left when a leaf falls from a twig. Leaf scars contain one or more dot-like scars called vascular bundle scars. The pattern of bundle scars along with the shape of the leaf scar can sometimes be used to determine the species of the plant.

More About StemsAcaulescent Having an inconspicuous stem.Caulescent Having a distinct stem.Woody Hard in texture, containing secondary xylem, and persisting for more than one growing season.Twining Spiraling around a support in order to climb.

Thorns, spines, pricklesThorn A reduced, sharp-pointed stem.Spine A reduced, sharp-pointed leaf or stipule or sharp-pointed marginal tooth.Prickle A sharp-pointed hair or emergence.

Gleditsia triacanthosThorns

Opuntia sp.Example of Spines

Rosa sp.Example of prickles