Classification of Plants
Classification of Plants, according to longevity plants are annual, biennial and perennial. According to stature, height, growth & duration of stems, plants are herbs, shrubs, trees, creepers,
twiners, climbers and lianas.
Classification of Plants on the basis of longevity
- Annual plants complete their life cycle within one year, e.g., Buttercup, Pea.
- Biennial plants complete their life cycle in two years – growing vegetatively and storing food in the first year; flowering and fruiting in the second year, eg., Henbane, Radish (in temperate areas).
- Perennial plants survive for several years, e.g., Canna, Zizyphus, Mango, Agave, Bambusa, Eucalyptus, etc. Some perennial plants ars also monocarpic, e.g., Agave,
Bambusa tulda, Melocanna bambusoides. They die after bearing fruits.
Classification of Plants on the basis of flower and fruit bearing cycle
- Monocarpic plants flower and fruit only once in life. All annuals and biennials are monocarpic. Some perennial plants are also monocarpic, e.g., Agave, Bambusa tulda, Melocanna bambussodies. They die after bearing fruits.
- Polycarpic are those perennial plants which bear fruits every year after attaining maturity, e.g., Mango, Artabotrys, Peepal.
Classification of Plants on the basis of Stem
- 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 are perennial plants with medium height woody stems but without any distinction of trunk. Shrubs often have several branches of equal height and are called
bushes e.g., Capparis, Rose
- Trees are tall perennial plants with a thick woody main stem or trunk. Trees are of three types:
- Caudex (Columnar): Unbranched trunk, e.g., Coconut Palm, Date Palm.
- Excurrent: Monopodial with one main stem or trunk from base to apex. Lateral branches giving a cone like appearance, e.g., Eucalyptus
- Deliquescent: The main stem or trunk is distinguishable only for some distance after it is replaced by a number of large branches which form a dome shaped crown., e.g., Mango, Dalbergia.
Classification of Plants on the basis of growth habit
- Trailers: Plants which spread on the ground without interval, e.g., Strawberry.
- Creepers plants spread on the ground, rooting at intervals, e.g., Strawberry.
- Twiners are weak-stemmed plants where the stem coils or twines around an upright support, e.g., Ipomoea cairica (Railway Creeper), Quisquails (Rangoon Creeper).
- Climbers plants climb up an upright support by special clinging or clasping structures like tendrils, roots and hooks.
- Lianas (Lianes) are woody twiners and climbers are called lianas. They are found in tropical evergreen forests, e.g., Phenera (=Bauhinia) vahlii, Hiptage.
- 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 posses hanging roots with hygroscopic outer spongy tissue called velamen.
The smallest angiosperm is Wolffia (a rootless aquatic). It has a diameter of 0.1 mm. The tallest plant is an angiosperm named Eucalyptus regnans. It reaches a height
of 114 m or 375 ft. Sequoia sempervirens (a gymnosperm) is the second tallest tree with a height of 111m. Gymnosperm usually possess more taller trees as compared to angiosperms.