Root tensile strength (Tr) is a fundamental root mechanical trait and serves as a key parameter for assessing the contribution of vegetation to soil stability. Tr is known to exhibit high intraspecific variability, but whether Tr varies with season remains unclear. Here, we investigated the seasonal variation in Tr in two commonly seen herbaceous species, i.e., Artemisia argyi and Cirsium setosum, both of which can be future candidates for revegetating species along roadsides in temperate and subtropical regions. We examined the Tr of their first- (closest to the stem base) and third-order lat-eral roots sampled in the southwest of Henan, China, in two distinct periods: September (late growing season) and December (dormant season).