Classification of Weeds


The weeds with similar morphological characters, lifecycle, requirements of soil, water climatic condition are grouped together as a class or category. It is always economical and practically feasible to manage the group of weeds as compared to manage the individual weed species.

According to Morphological Characteristics
  • Grasses - Nodes and internodes can be clearly seen. The stem is round and the middle of the stem consists of a bole. Internodes are hollow. Leaves are arranged alternatively in grasses. Also, have leaf sheath and leaf blade.

  • Sedges - There are no clear nodes and internodes of three flowers and any other leaves are in there. The stem is rectangular and solid.

  • Broadleaves - The leaves are broad and solid.

According to Life Cycle
Depending upon their life cycle weeds can be classified as,
  • Annual weeds - They complete their lifecycle within one year or one season.

  • Biennial weeds - They take at least two years or two seasons to complete their life cycle. They complete their vegetative growth in first year or season and produce flowers and seeds in the next year or season.

  • Perennial weeds - They continue or grow for more than two years.

According to Root System
Depending upon the root system perennial weeds are classified as
  • Shallow rooted perennials - Those perennial weeds having about 20 to 30 cm deep root system are called shallow rooted perennial weeds.

  • Deep rooted perennials - Weeds having about one meter or deeper root system.

According to the Place of Occurrence
Depending upon the place of their occurrence they can be grouped under,
  • Weeds of cropped lands
  • Weeds of pastures and grazing lands
  • Weeds along the water channel

According to Nature of Stem
  • Woody weeds
  • Herbaceous weeds


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