Fisher's next piece, Studies in Crop Variation II, written with Winifred Mackenzie and published in 1923, studied the variation in yield across plots sown with different varieties and subjected to different fertiliser treatments.
fˈɪʃɚz nˈɛkst pˈiːs, stˈʌdiz ɪn kɹˈɑːp vˌɛɹɪˈeɪʃən ɹˌoʊmən tˈuː, ɹˈɪʔn̩ wɪð wˈɪnɪfɹɪd məkˈɛnzi ænd pˈʌblɪʃt ɪn nˈaɪntiːnhˈʌndɹɪd twˈɛnti θɹˈiː, stˈʌdid ðə vˌɛɹɪˈeɪʃən ɪn jˈiːld əkɹˌɑːs plˈɑːts sˈoʊn wɪð dˈɪfɹənt vɚɹˈaɪəɾiz ænd sˈʌbdʒɛktᵻd tə dˈɪfɹənt fˈɜːɾəlˌaɪzɚ tɹˈiːtmənts.