Each year I plant poppy seeds in a field where I have removed perennial weeds by hand the previous year. This year a patch in the field seemed to be coming up with grass. But the grass turned into very tiny white flowers in the first week of June. Then a new set of flowers appeared in late June. AND... very few poppies appeared in this place. No new soil/fertilizer has been applied since a load of manure three years ago.

Any idea what this is, or how it appeared in such a concentration?

The first 3 pictures are from June 8. The last 2 are from June 26.

Note, these are not Quaker Ladies, which are bluish with 4 petals.