Table 3. Scale used to quantify damage where plants were present.

Rating	Rating description
0	Not associated with damage (e.g. just growing in soil or present beneath the soil)
1	Correlation with existing damage (e.g. emerging from a crack in paving or a gap in brickwork, but with no detectable variation away from baseline damage)
2	Minor exacerbation of existing damage (e.g. a detectable increase in crack width away from baseline damage)
3	Moderate exacerbation of existing damage (e.g. a detectable addition to damage away from baseline damage, i.e. new cracks forming around an initial crack)
4	Major exacerbation (damage beyond cracking, e.g. a damaged wall becoming undermined)
5	Causing minor damage (e.g. creating a crack)
6	Causing medium damage (e.g. creating a crack which has spread to form additional cracks)
7	Causing major damage (damage beyond cracking, e.g. a previous undamaged wall becoming undermined, or concrete hard standing being significantly lifted and cracked, or a roof being smashed in due to collapse)