Experimental hybridizations of Eriophyllum annuals (Asteraceae, Helenieae)

Seven of the eight annual species of Eriophyllum , a western North American genus, were studied in greenhouse and garden. Eriophyllum congdonii and E. nubigenum proved to be self‐compatible; E. ambiguum , E. multicaule , E. pringlei , and E. wallacei were self‐incompatible; E. lanosum was not studied. All combinations of artificial hybridizations were attempted except E. congdonii × E. lanosum . Among the species with n = 7, fertile hybrids came from E. congdonii × E. nubigenum and sterile hybrids from E. ambiguum var. ambiguum × E. pringlei , E. ambiguum var. paleaceum × E. congdonii , E. multicaule , E. nubigenum , and E. pringlei , as well as E. multicaule × E. congdonii and E. multicaule × E. pringlei . The other homoploid combinations failed, as did heteroploid combinations involving the annual species with n = 7 and either E. wallacei ( n = 5) or E. lanosum ( n = 4). Sterile hybrids were generated in crosses of E. congdonii to the perennial E. lanatum ( x = 8).