Solidago kralii Semple is native to sandy soils and can be locally common in scattered populations on in south central Georgia and near Augusta, Georgia and adjacent South Carolina. See Semple & Cook (2006 FNA) for a detailed description. Solidago kralii is slightly resinous over much of the plant and especially on the phyllaries, has multiple peduncle bracts, and broader leaves than S. plumosa. It can form dense populations in some places and be very rare in others. The species is likely closely related to S. austrocaroliniana known from a single collection from Union Co., South Carolina, S. plumosa from one population in North Carolina, and less so to S. arenicola from very rare populations in northern Alabama and north central Tennessee and adjacent Kentucky. The species was first described in 2003.
Solidago kralii is diploid 2n=18 throughout its range (Peirson et al. 2012).
Solidago kralii was included in the DNA study of S. subsect. Humiles (Peirson et al. 2013)
Semple et al. (2019) presented a multivariate analysis of all 13 species of S. subsect. Humiles. Solidago kralii was included in the analyses with 12 and 11 species (82% and 82% correct placment a posteriori) and in the analysis of the four species native to the southeastern US (70% correct placment a posteriori). It is the only species of subsect. Humiles native to Georgia (until someone discovers another rare species in the subsection).