hɪz stˈʌdiz ʌv wʌt hɐz sˈɪns bˌɪn nˈoʊn æz dʒˈuːnɪpɚpˈɛɹ ɹˈʌst ʃˈoʊd ðæt ðɪs fˈʌŋɡəs ˈænjuːəli swˈɪtʃᵻz bᵻtwˌiːn tˈuː hˈoʊsts; dʒˈuːnɪpɚɹəs sɐbˈiːnə ɪz ðə pɹˈaɪmɚɹi tˈɛlɪəl hˈoʊst ænd pˈɛɹ, pˈaɪɹəs kəmjˈuːniz, ɪz ðə sˈɛkəndɚɹi ˈiːʃəl hˈoʊst.
His studies of what has since been known as juniper-pear rust showed that this fungus annually switches between two hosts; Juniperus sabina is the primary (telial) host and pear, Pyrus communis, is the secondary (aecial) host.