Russian Knapweed (<i>Acroptilon repens</i>) (IMAGE) Cambridge University Press Caption This photograph is from Gaskin and Littlefield (Pp 119-124). It shows discrete Russian knapweed (Acroptilon repens) clones arising from a sea of cheatgrass. Each representing a distinct genotype that is maintained by asexual, vegetative reproduction. Photo taken near Bridger, Carbon County, Montana, in July 2015. Credit Jeffrey L. Littlefield. Usage Restrictions Please reference photo copyright if reused License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.