Classification of weeds - 7,8 and 9

 7. Based on morphology -

Based on the morphology of the plants the weeds are classified as follows :

a) Grasses :

All the weeds are come under the family poaceae are called as grasses which are characteristically having long narrow spiny leaves.

Ex. Echinocloa colonum

b) Sedges :

These weeds belonging to the family cyperaceae come under this group. The leaves are mostly from the base having modified stem with or without tubers.

Ex. Cyperus rotundus

c) Broad leaved weeds -

This is the major group of weeds as all other family weeds come under this except that is discussed earlier. All dicotyledons weeds are broad leaves weeds.

Ex. Tridax procumbens

8. Based on nature of stem -

Based on development of bark tissues on their stem and branches, weeds are classified as follows -

a) Woody weeds :

These are collectively called brush weeds.

Ex. Prosopis juliflora , Lantana camera

b) Semi-woody weeds :

Ex. Croton sparciflora 

c) Habaceous weeds :

These weeds are green succulent stem are of most common occurrence around us.

Ex. Amaranthus viridis

9. Based on specificity -

a) Poisonous weeds :

The poisonous weeds cause aliment on live stock resulting in death and cause great loss. These weeds are harvested along with fodder or grass and fed to cattle or while grazing the cattle consume these poisonous plant.

Ex. Datura metal

b) Parasitic weeds :

These parasitic weeds are either total or partial which means the weeds that depends completely on the host plant are term as total parasitic while the weeds that partially depends on host plants for minerals and capable of preparing it's food from the green leaves are called as partial parasites.

Ex. Orabanche cemua on Tobacco ( root parasit)