A wide range of alternative weed control methods exist. These include mechanical, ground covering, crop rotational, physical, biological, botanical, thermal and agroecological techniques.
Caution should be applied when selecting substitute herbicides to replace paraquat as they have their own hazards. Diquat, for example, is a close relative of paraquat and it is also acutely toxic to humans. These and several other widely used herbicides qualify as Highly Hazardous Pesticides (HHPs) for reasons including acute and chronic human health hazards, environmental toxicity or persistence.
Alternative methods are often best combined in Integrated Weed Management (IWM) strategies, suitable for specific cropping systems. Successful IWM methods to replace paraquat use and to reduce reliance on herbicides have been used with the following crops:
- Coffee – Making use of beneficial ground cover plants, combined with mechanical weeding, mulching at reduced frequency.
- Pineapple – Physical and biological methods to decompose crop foliage post-harvest (to prevent it serving as a breeding site for stable fly, a livestock pest).
- Tea – Herbicide-free integrated weed management know-how, centered on encouraging non-competitive ground covering plants.
- Oil palm – Combining other herbicides with methods including cover crops, mulches, manual or mechanical removal, weed exclusion sheeting, biological control and livestock grazing.
- Potato – Mechanical flailing for pre-harvest haulm destruction.