The disk floret's stigma stays closed while pollen is on it, keeping its ovary safe from self-pollination.
ðə dˈɪsk flˈɔːɹəts stˈɪɡmə stˈeɪz klˈoʊzd wˌaɪl pˈɑːlən ɪz ˈɔn ɪt, kˈiːpɪŋ ɪts ˈoʊvɚɹi sˈeɪf fɹʌm sˈɛlfpˌɑːlᵻnˈeɪʃən.