Sagina japonica is known from northern Ohio and southern Ontario (Rabeler 1996) and likely will be found in Michigan. It resembles S. procumbens somewhat, but is an annual with mostly 5-merous flowers and conspicuous glandular pubescence on the pedicels and upper stem.

1. Petals conspicuously exceeding the sepals; styles ca. 1-1.5 mm long.

S. nodosa

1. Petals much shorter than the sepals, very inconspicuous; styles less than 0.5 mm long.

S. procumbens