Western Late Goldenrod

Solidago altissima var. gilvocanescens (Rydb.) Semple is the common summer and fall blooming goldenrod of the Great Plains.  Its range extends eastward on the Prairie Peninsula in Illinois and Indiana (see map for S. altissima).  The inflorescence is broadly secund pyramidal like var. altissima, but the leaves tend to be more densely short hairy and the upper broadly lanceolate stem leaves are sometimes serrate with a few teeth (Semple & Cook 2006 FNA; as ssp. gilvocanescens).  Smaller headed plants (diploids) can be confused with S. canadensis var. hargeri in areas of sympatry.  The variety has been treated as S. canadensis var. gilvocanescens Rydb., S. gilvocanescens (Rydb.) Smyth, and S. canadensis subsp. gilvocanescens (Rydberg) Á. Löve & D. Löve.  In Texas, the variety may be confused with var. pluricephala, which has less densely hairy leaves.  Semple et al. (2015) found strong multivariate statistical support for recognizing the variety and discussed reasons why it is not treated as a separate species.  The variety is likely the ancestor of var. altissima and var. pluricephala.

The variety is diploid 2n= 18 and tetraploid 2n=36 with a few hexaploids 2n=54 (Semple 2022).  Ball galls occur on mid to upper stems of the variety.