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Classification of weeds - 7,8 and 9

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 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...
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Classification of weeds - 3,4,5 and 6

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  3. Based on soil type - a) Weeds of black cotton soil :  These are often closely allied to those grow in dry condition. Ex. Aristolochia bractea b) Weeds of red soil : They are like the weeds of garden land consisting of various classes of plants. Ex. Commelina benghalensis c) Weeds of sandy soil : Weeds that occur in soil having good drainage. Ex. Leucas sapera d) Weeds of laterite soil : Ex. Lantana camera 4. Based on origin - a) Indigenous weeds : All the native weeds of the contry are coming under this group and most of the weeds are indigenous. Ex. Acalypha indica, Abutilon indicum b) Exotic weeds : These are weeds introduced from other countries. These weeds are normally troublesome and control becomes difficult. Ex. Partherium hysterophorus, Acanthospermum 5. Based on cotyledon - These are classified in to two type- a) Monocots  :  Ex . Crotalaria verucosa b) Dicots :  Ex. Paricum flavidum, Echinochlora colona 6 . Based on soil - These are classified...
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Classification of weeds

  Classification of weeds                    Out of 2,50,000 species, weeds constitute about 250 species which are prominent in agricultural and non-agricultural system. Under world conditions about 30,000 species is grouped as weeds.                  Classification of weeds based on - 1. Life span 2. Ecological affinities 3. Place of occurrence 4. Origin 5. Soil pH 6. Specificity 7. Morphology 8. Cotyledon number 9. Soil type (edaphic) 1 Based on life span :- a) Annual weeds - Weeds that live only for a year and complete their life cycle in that year. Ex. Commelina benghalensis, Boerhavia erecta Chenopodium album  b) Biennial weeds -   It completes the vegetative growth in the first season, flower and set seeds in the succeeding season and then dies. Ex. Alteramanthera echinata, Daucus carota  c) Perennial weeds - They live for more than two years and may live almost ...
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