According to texture, height, growth and duration of stems.
plants are herbs, shrubs, trees, creepers, twiners, climbers and lianas.
Herbs- Herbs are small plants with soft and pliable stems. Herbs can be
annual (e.g., Buttercup). biennial (e.g., Henbane) and perennial (e.g.,
Canna).
Shrubs- Shrubs are perennial plants with medium height.
woody stems but without any distinction of trunk. Shrubs have oftenly
several branches of equal height arising from base and are called
bushes. e.g., Capparis, Rose.
Trees- They are tall perennial plants with a thick woody
main stem or trunk. Trees are of three types:
a) Caudex (= columnar).
unbranched trunk with crown of leaves e.g., Coconut. Palm. Date Palm '.
nalm like habit is called arborescent.
b) Excurrent. Monopodial with
one main stem or trunk from Loss to apex. Lateral branches giving a cone
like appearance. e.g., Eucalyptus.
c) Deliquescent. The "main stem or
trunk is distinguishable only for some distance after which it is
replaced by a number or large branches which form a dome-shaped crown
e.g., Mango, Dalbergia. Ficus (Banyan).
CuIm : is unbranched jointed stem
with distinct nodes and internodes. Nodes are usually solid while
internodes are hollow e.g.. Bamboo.
Trailers: They are plants which spread on the ground without
rooting at intervals, e.g., Tribulus , Euphorbia prostrata.
Creepers: The plants spread on the ground. rooting at intervals, e.g., Strawberry.
Twiners. They are weak-stemmed plants where the stem coils
or twines around an upright support. in dextral or sinistral manner.
This coiling is genetic. e.g., Ipomoea cairica (Railway Creeper).
Quisqualis (Rangoon Creeper).
Climbers. The plants climb up an upright support by special clinging or clasping structures like tendn’ls. roots and hooks.
Lianas (= Lianes). Woody twiners and climbers are called
lianas. They are found in tropical even green forests. e.g., Phanera (=
Bauhinia) , Hiptage.
Epiphytes: Epiphytes are plants which live on other plants
for space only. They are. therefore. also called space parasites,
Angiospermic epiphytes commonly live on trees. e.g., Vanda, Dendrobium.
They often possess hanging roots with hygroscopic outer spongy tissue
called velamen to absorb moisture.Vanda is first terrestrial and then becomes epiphyte.
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