Hyssop-leaved Thoroughwort (Eupatorium hyssopifolium) 2015-9-30 Bombay Hook NWR, DE

-several stems arising from the base
-some leaves nearer the base almost look whorled to me
-some leaves near the middle of the plant have leaves (fascicles?) in the axils
-some leaves near the middle of the plant are alternate - possibly the leaves of the (fascicles?)
-leaves at the top of the plant where flowering takes place are opposite

http://plants.usda.gov/java/largeImage?imageID=euhy_001_avd.tif
http://www.marylandbiodiversity.com/viewSpecies.php?species=4273
http://capemaywildlife.com/_templates/group_eupatorium.html
1-5 disk flowers:
https://gobotany.newenglandwild.org/species/eupatorium/hyssopifolium/

the following thoroughworts I might see and don't have yet, are at:
http://capemaywildlife.com/_templates/group_eupatorium.html
Late-flowering Thoroughwort (Euatorium serotinum)
White-bracted Thoroughwort (Eupatorium leucolepis)
White Thoroughwort (Eupatorium album)
Rough Boneset (Eupatorium pilosum)

long list of Eupatorium:
http://luirig.altervista.org/flora/taxa/floranam.php?genere=Eupatorium