1. List effects of chemical control of

Question

weeds.
2. Mention three effects of bush
burning.
3. State three (3) effects of
mechanical/ physical control of
weeds.

Answer 1

1. Effects of chemical control of weeds:
- Increased crop yield by reducing weed competition for nutrients, water, and sunlight
- Reduced labor costs by eliminating manual weeding
- Contamination of soil and water sources if herbicides are overused or not used properly
- Development of herbicide-resistant weed species
- Harmful effects on non-target organisms such as beneficial insects and wildlife

2. Effects of bush burning:
- Destruction of natural habitats and loss of biodiversity
- Air pollution from smoke and greenhouse gas emissions
- Soil erosion and loss of soil fertility due to destruction of vegetation cover

3. Effects of mechanical/physical control of weeds:
- Time-consuming and labor-intensive compared to chemical control methods
- Damage to crop plants if not done carefully
- Temporary control of weeds as they may grow back quickly if roots are not completely removed