Hieracium abscissum f. hypoglossum Zahn accepted as Hieracium abscissum Less. (original description)
Hieracium adenocephalum var. subsetulosum Zahn accepted as Hieracium streptochaetum Zahn (original description)
Hieracium albiflorum f. lyallii Zahn (original description)
Hieracium albiflorum subvar. rosendahlii Zahn (original description)
Hieracium albiflorum subvar. sanhedrinense Zahn (original description)
Hieracium avilae var. novogranatense Zahn (original description)
Hieracium babcockii Zahn (original description)
Hieracium babcockii var. setosiceps Zahn (original description)
Hieracium bangii subsp. bangii Zahn accepted as Hieracium bangii Rusby accepted as Hieracium leptocephalum Benth. (original description)
Hieracium bangii var. siambonicum Zahn accepted as Hieracium leptocephalum Benth. (original description)
Hieracium boliviense subvar. glabrescens Zahn (original description)
Hieracium boliviense var. genuinum Zahn (original description)
Hieracium carolinianum f. alpestre Zahn (original description)
Hieracium carolinianum f. glabrescens Zahn (original description)
Hieracium carolinianum f. normale Zahn (original description)
Hieracium carolinianum f. pinetorum Zahn (original description)
Hieracium carolinianum f. virescens Zahn (original description)
Hieracium carolinianum subsp. alleghaniense Zahn (original description)
Hieracium carolinianum subsp. carolinianum Zahn accepted as Hieracium carolinianum Fr. (original description)
Hieracium carolinianum subsp. domingense Zahn (original description)
Hieracium carolinianum subsp. rugelii Zahn (original description)
Hieracium cascadorum Zahn (original description)
Hieracium chelannense Zahn (original description)
Hieracium chilense var. navarinum Zahn accepted as Hieracium patagonicum Hook.f. (original description)
Hieracium comatum var. filipense Zahn (original description)
Hieracium commersonii f. floccosius Zahn (original description)
Hieracium commersonii f. subefloccosum Zahn (original description)
Hieracium commersonii f. verum Zahn (original description)
Hieracium commersonii subvar. amphifloccum Zahn (original description)
Hieracium commersonii subvar. hypofloccum Zahn (original description)
Hieracium commersonii subvar. latifolium Zahn (original description)
Hieracium commersonii subvar. normale Zahn (original description)
Hieracium commersonii subvar. subpilosum Zahn (original description)
Hieracium commersonii var. genuinum Zahn (original description)
Hieracium commersonii var. hypochaetophorum Zahn (original description)
Hieracium commersonii var. kingii Zahn (original description)
Hieracium commersonii var. lorentzii Zahn (original description)
Hieracium crepidispermum f. majoriceps Zahn accepted as Hieracium schultzii Fr. (original description)
Hieracium crepidispermum f. minoriceps Zahn (original description)
Hieracium cusickianum Zahn (original description)
Hieracium erianthum f. aequatorianum Zahn (original description)
Hieracium erianthum f. normale Zahn (original description)
Hieracium erianthum var. kunthii Zahn (original description)
Hieracium eriosphaerophorum var. castillense Zahn (original description)
Hieracium frigidum var. jubatum Zahn (original description)
Hieracium horridum subsp. horridum Zahn accepted as Hieracium horridum Fr. (original description)
Hieracium horridum subsp. relicinum Zahn (original description)
Hieracium horridum var. breweri Zahn (original description)
Hieracium horridum var. genuinum Zahn (original description)
Hieracium ignatianum var. glaziovianum Zahn (original description)
Hieracium jaliscense var. eriobium Zahn accepted as Hieracium pringlei A.Gray (original description)
Hieracium leptocephalum var. leptocephalum Zahn accepted as Hieracium leptocephalum Fries ex Omang (original description)
Hieracium leptocephalum var. microcephalum Zahn (original description)
Hieracium lorentzianum var. subtucumanicum Zahn accepted as Hieracium niederleinii (Zahn) Sleumer (original description)
Hieracium marylandicum Zahn (original description)
Hieracium mexicanum f. glabrescens Zahn accepted as Hieracium mexicanum Less. (original description)
Hieracium mexicanum subsp. mexicanum Zahn accepted as Hieracium mexicanum Less. (original description)
Hieracium mexicanum subsp. niveopappum (Fr.) Zahn accepted as Hieracium mexicanum Less. (original description)
Hieracium mexicanum subsp. praemorsiforme (Sch.Bip.) Zahn accepted as Hieracium mexicanum Less. (original description)
Hieracium pacificum Zahn (original description)
Hieracium paraguayense var. chacoense Zahn accepted as Hieracium chacoense (Zahn) Sleumer (original description)
Hieracium parryi var. chaetobrachion Zahn (original description)
Hieracium peruanum var. ayavacanum Zahn accepted as Hieracium peruanum Fr. (original description)
Hieracium peruanum var. genuinum Zahn (original description)
Hieracium plicatum var. genuinum Zahn (original description)
Hieracium smolandicum subsp. robinsonii Zahn accepted as Hieracium robinsonii (Zahn) Fernald (original description)
Hieracium streptochaetum subsp. streptochaetum Zahn accepted as Hieracium streptochaetum Zahn (original description)
Hieracium stuebelii var. consacae Zahn (original description)
Hieracium triste var. tristiforme Zahn accepted as Hieracium triste Willd. ex Spreng. (original description)
Hieracium venosum var. blombergii Zahn (original description)
Hieracium warmingii var. lechleri Zahn accepted as Hieracium mosenii Malme (original description)
Hieracium wrightii var. genuinum Zahn (original description)
Hieracium wrightii var. palmeri Zahn accepted as Hieracium schultzii Fr. (original description)