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Comments:  The sunflower (Helianthus) plants found during the survey of the gorge and rim trails at Buttermilk Falls State Park (BFSP) are most similar to Helianthus tuberosus and H. decapetalus.  However, they don't strictly conform to the scientific guidance* for either of these two species.  Most treatments of this group of species differentiate between these two, very similar species based on stem characteristics.  Helianthus tuberosus has stems that are evidently hairy throughout, with rough, stiff hairs.  Helianthus decapetalus has stems that are more or less hairless, except within the area of the inflorescence.  Moreover, stems of H. decapetalus are typically glaucous, compared with stems of H. tuberosus, which are not glaucous.  Regarding other characteristics, the involucral bracts of both species tend to be long and thin, with ciliate margins and tend to lean outwards (loose, not appressed), but the bracts of H. tuberosus are often dark-tinged (blackish), compared with those of H. decapetalus, which are completely green.  The bracts of H. tuberosus usually spread outwards from the middle, while those of H. decapetalus tend to lean outwards from the base.  There are no other Helianthus species which closely match the characteristics of the plants found at BFSP.  Coincidently, there is a large, robust population of H. tuberosus found upstream from the gorge area (within the "upper park" section of BFSP).  Those plants more readily conform to the scientific guidance for that species, and significantly differ in morphology from the plants found within the surveyed area.  In sum, we cannot be confident of our identification of the Helianthus plants found within the survey area (gorge and rim trails), though our plants more closely conform to the guidance for H. tuberosus.
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