The weeds act as competition for the same space and nutrients that crops need to grow. If these weeds are ignored and was let to grow, the farmer will more often than not get lower grain yeilds.
The weed can be a great hindrance to the growth of the crops since it will be a competitor of the plant for nutrients. The roots of the weed and crop will compete in absorbing nutrients from the soil. This will cause a less healthy plant causing a lower yield for the farmers. It will invade crops and will cause lesser output for the farmers.
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