Synthetic fibres are inorganic while non-synthetic textiles can be organic.
Organic fibres provides nutrition to the lichen, while all kinds of
fibres make good places for damp and dirt to accumulate –which
also gives nutrition to the affections.
The spores get easily hold in the sun blinds' fibres and when they have
got a foothold, they are very difficult to get rid of.
Lichen that has got hold recurs as long as the sun blinds contain spores
or remainders of affection. The affections must be sterilized and the
textiles must be disinfected for the affection to stop growing.