I live in Ontario, near Toronto and there's this plant which grows as a 'weed' in lawns I'd like to identify.
It usually shows up in lawns or in the cracks between pavements in late summer to autumn. It forms these fluffy masses, and when mowed acts as a kind of loose ground cover.
It produces tiny seeds that the sparrows like to eat.
The leaves are approx 10-15 mm in length.