Solidago canadensis (a.k.a.
Euthamia) is a perennial, rhizomatous (clonal) species, lacking basal leaves or with basal leaves reduced and early deciduous. It is widespread in North America, where it is found in most states in the US (excluding the extreme southeastern states) and most Canadian provinces (excluding Nunavut) (USDA 2010). In BC, it is a widespread, summer flowering species that is typical of old field conditions (that is, undisturbed successional sites). There are 3 recognized varieties in the province: var.
subserrata (primarily coastal in distribution), var.
gilvocanescens ( mainly interior plants), and var.
salebrosa (coastal and interior plants). These are separated based on flower (bract) characteristics and leaf hairiness. However, note that
Flora North America now recognizes only two varieties in North America (FNA 2010). This species was introduced to Europe in the 17th century, and is now invasive (Van Kleunan and Schmid 2003). It is now a significant invasive species in China.
Earliest observed flowering date in BC: July 10th, 2009, near Hope (personal observation).
References:
FNA. 2010. Solidago canadensis treatment. Flora North America. Available Online.
USDA. 2010. Plant profile for Solidago canadensis. United States Department of Agriculture. Available Online.
Van Kleunen, Mark and Bernhard Schmid. 2003. No Evidence for an Evolutionary Increased Competitive Ability in an Invasive Plant. Ecology 84 (11):
