Weeds:

• Refers to plant out of place or out of time.
• Are adapted to manmade habitats and interfere with human activities.
• Ruderals refer to plants occurring on earth heaps, dung hills, trash deposits, and so on.
• Environmental weeds refer to introduced, aggressive species that colonize natural vegetation and suppress the native species to a certain extent.
• Parasitic weeds refer to Cuscuta and Orobanche.

Types of weeds:

a) Agrestals:

• Weeds of cropland.
• Eg: Rice weed, Wheat weed, Pulse weed.

b) Ruderals:

• Refers to plants occurring on earth heaps, dung hills, trash deposits, and so on.

c) Grassland weed:

d) Parasitic weed:

• refer to cuscuta and orobanche.

e) Forestry weed:

f) Aquatic weed:

Economic importance of weeds

• As food.
• Fodder
• Medicines
• Botanicals
• Decorative ( Pistia, Eichornia, Lantana)

Medicinal weed of cropland

i) Marijuana

ii) Cannabis: Physical weakness

iii) Amaranthus: Paste in wounds or cuts.

iv) Cynodon dactylon (Dubo): Excess bleeding during mensuration.

v) Touch me not: Keep in mouth for toothache and dental problems.

vi) Solanum sps: Rheumatism.

Vii)Euphorbia: Wounds and cuts.

viii) Ocium bascilium: Cough.