Methods of weed management

1. Preventive measures:

• Avoid using crop seeds that are infested with weed seeds.
• Avoid feeding materials containing weed seeds to the farm animals.
• Avoid contamination of manure pits.
• Clean the farm machinery and other tools thoroughly before moving it from one field to the another field.
• Avoid shifting of soil, gravel and sand from weed-infested area to clean area.
• Keep the banks of irrigation channel, fence line and uncropped area clean.
• Strictly follow weed control laws, and quarantine measures.
• Use vigilance at each and every stage of crop growth.
• Do not use fresh or undecomposed organic manures containing viable weed seeds.
• Do not use organic mulches containing weed seeds.
• Apply the quarantine laws and regulations properly during the entry of seeds and propagules.

2. Curative measures

a) Eradication method

This method is followed when and where a new species is found it must be destroyed immediately before its multiplication, dispersion and acclimatization. Eradication can be done by:

i) Destroying the species at the initial stage of introduction or early growth stage.

ii) Degenerate the buried dormant but viable seeds by fumigation, flooding, heating and other methods.

b) Control method

i. Physical or mechanical destruction methods: Includes tillage, hand pulling, hoeing, sickling and mowing, flooding, burning, mulching with non-living materials etc.

ii. Good crop husbandry methods: These practices are good land preparation or tillage, growing smother competitive crops (sunnhemp, cowpea and rice bean), mulching, crop rotation and land rotation, intercropping, stale seed bed technique, pre sowing irrigation, summer fallowing or solarization, use of minimum tillage, green manuring, puddling, selection of adaptable variety, optimum date, use of quality seed, seed treatment, seed rate and method of sowing, stale seed bed, skipping the basal dose of fertilizer, correction of soil reaction, insect, pest and disease management, appropriate method and time of harvesting etc.

Limitations:

1. Labor intensive method.
2. It required timely operation.
3. Usually limited by either too wet or too dry soil when crop needs weeding, depending upon the weather conditions.
4. Soil should be workable.

iii. Chemical methods or application of herbicides and

iv Biological control methods: