Vernonia cinerea (above and below). This weed is commonly growing in marginal lands or on roadsides. The branching and thin plant is short at only around one foot tall. It is just attractive because of the purple minute flowers. This is reported to have anti malarial properties as shown by this studies.
As the flower matures and about to dehisce, the seedheads are spherical and lovely.
NOID (above and below)
close-up of Euphorbia hirta