plant morphology

annual

plants living for one year or less (one growing season)

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entire life cycle from seed to flower within one growing season (germinate, bloom, set seed, and die all in one year)

biennial

plants living for two years, typically flowering and fruiting the second year (germinate and grow one year, bloom and die following year)

perennial

plants living for three years or more (grows and flowers for many years)

• asparagus (herbaceous perennial)

• pine (woody perennial, grows every year above ground and underground)

• herbaceous perennial: above ground part dies at end of the season, underground part is still alive

deciduous

plants which shed all their leaves at the end of each growing season, applied to plant parts which fall off

• oaks, maples, beeches

• when leaves fall off, energy can be focused on woody growth (advantage)

evergreen

remaining green during the dormant season, plants never without leaves

herbaceous perennial

above ground part dies at the end of season, underground part is still alive

woody perennial

grows every year above ground and underground

woody plants

plants with live above-ground stems, increase with size each year

• shrub

• tree

• liana

shrub

woody plants with more than one stem rising from the ground

tree

woody plants with single main stem/trunk

a small tree is usually less then 15 feet tall

liana

woody plants with elongate, flexible, non-self-supporting stem

• english ivy, grape vines

• woody climbing plants that are climbing onto trees typically

decumbent

branches come upwards

procumbent

branches on ground, don’t come up

plant parts

1. roots

2. stems

3. leaves

4. flowers

5. fruits

6. seeds

roots

• underground portion of plant

• major component in terms of function and absolute bulk (dry weight)

• anchors plant, essential for nutrition and water uptake, food and storage

root systems

taproots and fibrous roots

taproots

• main root axis and smaller branches

• main root axis from which smaller root branches arise

• priary root that more or less enlarges and grows downward

• usually go very deep

fibrous roots

• root system with all branches of roughly same thickness

• root system where all roots are about the same size

• not dominating root

fleshy roots and tuberous roots

fleshy roots

relatively thick and soft fibrous roots (daylily)

tuberous roots

enlarged with storage tissue (sweet potatoes)

examples of three other roots

heart root, flat root, aerial root

stems

• main axes of plant

• have nodes and internodes

• usually have leaves with buds in leaf axis

• may bear flowers (fruits)

six features of stems

1. main body

2. support branches

3. leaves

4. flowers

5. fruits

6. transport carbohydrates, nutrients, water

bark

outermost layers of woody stem, including all living and nonliving tissues external to the cambium

can be smooth, scaly, colorful

nodes

position on stem where leaves and branches come from

internode

portion between two nodes

leaf scar

scar remaining on branch after leaf falls

lenticel

slightly raised, slightly corky, lens-shaped area on surface of stem

* lens-shaped warlike patches of paranchymatous tissue on surface of stem

pith

spongy, parenchymatous central tissue in stems

three types

1. continuous (solid)

2. chambered

3. diaphragmed

continuous pith

solid throughout

chambered pith

tissue between plates has disappeared

diaphragmed pitch

continuous pitch with firmer cross plates at intervals

collateral bud

lateral to axillary bud

superposed bud

located immediately above axillary bud

adventitous bud

developing from somewhere other than node or tip of a stem

dormant bud

inactive; maybe due to dry weather or winter condition

flower bud (reproductive bud)

containing or producing embryonic flower(s)

leaf bud

containing or producing leaves

vegetative bud

containing embryonic leaves (stems) and flowers

scaly bud (covered bud

covered by bud scales

naked bud

not covered by bud scales

infrapetiolar bud

axillary bud surrounded by base of petiole

pseudoterminal bud

axillary bud immediately next to terminal bud

bud scale scar

scar remaining after bud scales fall

eight modified stems

1. bulb

2. corm

3. rhizome

4. runner (stolon)

5. scape

6. tendrils

7. thorn

8. cladophyll

bulb

short, basal, underground stem surrounded by thick fleshy leaves

corm

a shoft, upright hard or fleshy bulblike stem, usually covered with paper, thin, dry leaves

rhizome

horizontal, prostrate, or underground stem with reduced scalelike leaves

runner (stolon)

horizontal aboveground stem, usually rooting and producing plants at nodes

scape

leafless peduncle arising from ground levek, sometimes with small scale-like leaves

tendrils

small, twisting appendage that attaches a scandent plant to other plants or subjects

thorn

reduced, sharp, pointed stem

cladophyll

stem with form and function of a leaf

trunk

main stem of tree below branches

twig

small shoot or branch from a tree

prickle

sharp pointed extension of cortex and epidermis