Highways England should be required to plant more greenery around, or in the middle of, highways with available space. The RHS has found that Cotoneaster is at least 20% more effective than other shrubs at reducing pollution. Alternatives could also be considered.
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With coronavirus restrictions lessening, the common trend shows that cars will begin to return to the roads, increasing the surrounding pollution. The problem of air pollution has been worked on in some areas, especially in London with the Ultra-Low Emission Zone. However, more could be done on roadsides. Some highways have vast amounts of empty space that could be filled with greenery.